Responses in red. I liked a lot of what I saw in this developer diary, though it was a bit alarming to see the devs say that they actually started with less freedom and had to scale back into more player freedom.

Communion of Scribing: The Reconstruct Spell as a Spell-Like Ability
As Repair spell; great. I saw (no citation at the moment however) that Vargouille confirmed this will be an SLA for any Bladeforged, not added to the paladin spellbook etc. as people were wondering.

As many noted, racial self-healing a la Jorasco dragonmarks--but presumably with the advantage of not having the far inferior 'per day' aspect and the ability to apply spellpower and metamagics--will make this a very powerful ability.

Communion of Handling: Your attached weapon becomes Adamantine, bypassing Adamantine damage reduction.
Nice, and also presupposing they will be getting some or all of the standard warforged post-enhancement pass enhancements.
Power of the Forge: Action Boost: For 20 seconds, you gain:
+20% Action Boost bonus to weapon damage.
+30 Action Boost bonus to Universal Spell Power.
+4 Action Boost bonus to all Saving Throws. While under this effect you do not automatically fail saving throws on a roll of a natural 1.
+10 Action Boost bonus to Armor Class and Physical Resistance Rating.
Seems quite powerful, and I'd presume it'd be a lvl 20 racial capstone clicky? It's the equivalent of a one-click activation of low level Damage Boost, Draconic Fury, Save Boost, Armor Boost, and a PRR boost. Quite good.

As everyone can already see, the Bladeforged have some of the best art of DDO in general, so I'd purchase them just for that.

Morninglord Weapon Training: Grants you +1 to attack and damage with morningstars, maces, and hammers. Grants +1 to attack and +2 damage with mauls.
Unfortunate that this doesn't just include all blunts but then we'd probably be flooded with monk-splashed Morninglords wielding quarterstaves and fists. Not that it would be a bad thing, but I think the boost to underutilized weapon classes--particularly mauls here--is a step in the right direction. Of course, some truly decent named hammers/mauls in all level ranges will help (currently, Mornh/Maul of Malice/Coronation and just a few other hammer/maul class weapons are the only truly good specimens I can think of).
Blessing of Amaunator: You gain use of the Blessing of Amaunator spell-like ability which acts as Aid Mass, Spell Resistance Mass, and Deathward Mass.
Pretty good particularly if you don't go the divine route with your Morninglord. A CL20 DW/Aid/SR clicky for any non-divine is a nice convenience clicky in lieu of ~3 Visors in the backpack.
Amaunator’s Brilliance: Spell Like Ability: Sunburst: A globe of searing radiance explodes to blast targets for 6 to 36 points of light damage in addition to blinding them. Oozes and Undead instead take 4 to 6 points of light damage per caster level. A successful Reflex save reduces the damage by half and negates the blindness. The save DC for this spell is based on your Wisdom. Light fearing undead may be instantly destroyed by this spell. Uses spell points. Cooldown decreases with each rank gained.
I personally really like Sunburst but one would have to see what the cooldown looks like before getting excited. Having a heightenable Sunburst SLA along with Command SLA seems like quite a bit of cheap CC for divines.

Of all the iconics, the Morninglords have the least snazzy new graphic. If you're not already bored with the elf physique with drow and elves, here's another slim, pointy-eared fixture of the mundane for you.

It's possible that they have some interesting cosmetic items that only they can use, or some such feature.

I would be very interested in seeing how various wisdom-based builds such as (acrobat/paladin/druid/ranger____) monks, druids (particularly if the Sunburst SLA from Season's Herald is on a separate timer), zen archers and the like will synergize with these abilities.

Purple Dragon Knight
Cormyrian Knight Training: You now use Charisma or Strength (whichever is higher) for Hit and Damage with shortswords, longswords, bastard swords, and greatswords.
This seems extremely powerful. Not only does it cover more desirable weapon classes (short sword, bastard sword, and greatsword--long swords are ****, and believe me I've tried using them all), but in one fell swoop allows for To Hit/Damage with a mental modifier.

The ability to create a CHA-meleeing Vulkoor Favored Soul, Lord of Blades Favored Soul, tank-oriented bastard+shield sorcerer, and all manner of CHA-based paladin with this seems extremely promising.

Rallying Cry: Action Boost: You and all allies within your aura gain +20% movement speed, a +(1/2/3) Morale bonus to Saving Throws. This ability can be used while feared, and dispels fear effects.
Seems like a useful clicky for low levels with very diminishing returns at higher levels (+30% striding negates, GH negates).
“For Cormyr!”: Once per rest, heal completely. If you are below 25% of your maximum hit points when this ability is used, you and all nearby allies gain your CHA modifier to hit and damage.
Self-healing racial ability, depending on cooldown, is again quite nice and opens up a lot of flexilibity for builds.

As far as looks go, PDKs look vaguely brutish with their bulky physique and ponderously large heads. It's nice to have a new human skin, though, so I'm all for it.

If only DDO had a weight/build option in character creation (and perhaps a burlap sack for H-Elf heads).

Winter Favored – You now resist 5 Cold damage, and your sneak attacks deal 1d6 extra Cold damage.
Thematically interesting but resistible sneak attack damage augmentation is merely okay compared to the abilities the other iconics get. Moreover, I'd rather have more shadow effects with Shadar-kai than cold effects, shrug. Even replacing this with a % chance to cripple or slow would be more desirable to me.
Shadow Jaunt – You become invisible and rush forward. You are ethereal to monsters while Jaunting. Invisibility lasts for six seconds.
Pretty awesome, and I assume the mechanic is kind of like Unearthly Reaction's/Ubiquity phasing. Cooldown is a major factor here, though.
Upgraded Spiked Chain Attack: Attack all nearby enemies multiple times over several seconds, causing them to bleed, and knocking them down on a failed Reflex saving throw.
Thematically seems rather disjunct--again, I'd prefer another shadow ability of some sort. Depending on the graphic, it could be either really neat or just odd. Depending on what can affect the Reflex throw (Dex mod? Vertigo items?) this ability could be kind of useful.

All in all, the Shadar-kai seem to have the least flashy and cohesive set of abilities, but I do think that their aesthetic is really cool.

Apart from the obvious rogue roll they'll fill, I'd be excited to try out monk, tempest, deepwood stalker, wolf/bear shapeshifted, and other dex-synergizing builds with them.

True Reincarnation
Kyle: Are Iconics able to use True Reincarnation?
Athena: We are focusing on the quality of the Iconic play experience first. While it's not included with the initial release, TR is recognized as a top priority. Ideally, we'll offer additional build flexibility first, with Lesser Reincarnation, which will allow you to change your base class in the near future.
The player base has made it abundantly clear that Iconic sales and popularity will be crippled without a TR option. I personally am very interested in Iconics in any case but I'd 100% hate to roll another character out of the 22 I have currently just to experience Iconics and then have nothing else to do with them.

Kyle: What came first when creating the Iconics, the story or the mechanics?
Ben: Creating the Iconics was a lot like coming up with characters you'd want to play in a tabletop D&D game. We're offering a character with a little back story and saying, "Here, you're free in the world and you can play any quest you want." For instance, the Purple Dragon Knight usually has obligations to serve and do all this stuff that a lot of players wouldn't be interested in doing, so our Purple Dragon Knight has something of an out clause; he or she is freed from service, but disgraced, and they have this one mission about clearing their name, but they can just do whatever they want.
Roleplaying considerations of any kind in DDO? Thrills me :]