Minecraft 1.5 and Canary b5Shadow386 on 04/19/11
"The team has begun work on Canary b5, so please do not open threads asking for an update. It will take time, so please be patient."
I believe that Canary b5 should be updated within the next five days.
For now we would like everyone to be patient, and if you can, downgrade to Minecraft 1.4_01.
Regards
-Ghostie
P.S We will be posting a link to a downgraded version of Minecraft in the near future.