I'm playing with my friends on a server on 14w25b but its a bit buggy. I dont really care but maybe other players.
Firstly:
The Item Frames seem to be very dark all the time I place them but the items in it just look fine. Whereas if you place it on a glowstone lamp it looks still kinda dark but its fine.
Secondly:
The map I made crashed when I entered, and later on leaved the nether. But after some time it worked again.

Good luck and keep on updating minecraft!