Bards are certainly not useless. But they are one of the weaker classes in the game. And, the things they can do best, is often not noticed by other players.
+7 damage (Inspire Courage song with Inspired Damage enhancement)
+9 attack (Inspire Courage song, Inspire Greatness song, Inspired Attack enhancement)
+4 Saves (Inspire Heroics song)
+4% dodge (Inspire Heroics song)
Most players aren't going to notice any of that. DPS is going to be thinking is "Man, my build rocks, look at all this damage I'm doing". Healers are going to be thinking "I'm all over this" (especially if they don't notice the bard helping with healing).
Personally - I'm playing a bard now for the first time ever. But, I always like to have a bard in the party. Not only are the songs nice - but they have the extra bonus of not being removed by beholders. They're usually good off-healers, and if specced right are good main healers. If the group is struggling, their CC can make the difference between a wipe and success. If the group is zerging through, then their damage is good enough to be a noticeable contribution.
Bards certainly could use some love from the devs. But, they are far from useless.