WoW news-3.20,2009- WoW has updated the Ulduar test schedule on the North American realms and put up some quick question and answers at forum.

The current schedule for Ulduar PTR testing:
Kologarn - Thursday Night, March 19, starting at 7pm EDT/4pm PDT.
Mimiron - Friday Night, March 20, starting at 7pm EDT/4pm PDT.
Iron Council - Saturday Night, March 21, starting at 7pm EDT/4pm PDT.
Flame Leviathan - Sunday, March 22, starting at 2pm EDT/11am PDT.

Quick Ulduar FAQ:
Q) Where's all the trash?
A) Trash has now been completed, and players will see the trash associated with each boss during their tests.
Q) Where's the loot? (UPDATED)
A) All loot should be present, except for some loot on trash creatures.

Q) What about achievements? (UPDATED)
A) We're still working on achievements, but many of them are now active and functional. Some achievements still have placeholder values.