On my 14w05b server ( I just transitioned from a to b today), I launched the jar file to open the server and logged on, and behold, every item frame (and item that was in them) and painting was floating on the ground *That did not have a block in front of it*. My item frames behind glass panes were moved in front of the panes ( they were on the same block coordinates). That being said, I guess the game is misplacing the coordinates of the item frames and paintings. I do not have a screen shot.
There are also gray particle effects in the corners, but that bug has been reported.
Sincerely, a heavy item frame user who does not want his items to despawn.