I'm not certain if any of the other realms are experiencing it, but Khyber is experiencing bouts of burst-lag that causes players to freeze in place and "rubber band" about as they attempt to fight against the lag.
This seems to occur mostly in common areas, but I have experienced this in instances as well.
The most recent occurrence was 4:30PM EST today, in Gianthold city (/loc output: (Standard): You are at: r1 lx1142 ly571 i311 ox122.15 oy68.51 oz220.03 h125.2) and seemed to clear up about 10 minutes later. Some bouts of this lasted in excess of 40 minutes (it was in a Gianthold Tor run just after we downed a dragon and we didn't want to abandon our chances at loot!)
I'd submit an in-game bug report, but well, the system is broken and brings me to the turbine support/account support ticket system. (I hope the new system comes soon!)