Kisirani's thread on the official forums lays out a few things: First, a lot has changed since the early PTR. This means that if you only did the quests in the first week or two of the Tournament, you should try them again before submitting feedback. If you've never been to the Tournament before, Jean Pierre Poulain awaits you on Krasus' Landing in Dalaran. He'll send you out there for free. If you want to do it yourself, the Tournament is just north of Sindragosa's Fall.
What kind of feedback are they looking for here? Kisirani says: "Whatever feedback you have to share. Bugs, balancing issues, clarity of purpose, overall feel, portions you particularly like or dislike, quests you find too difficult or easy, how the fights feel against NPCs or other players... let us know your thoughts on the Tournament."
If you're on the PTR and Ulduar hasn't been on your radar, I think this is a good opportunity to make a difference. The Tournament is going to be the new hotspot for solo play, and it should prove to be great fun... if it works. So let's make sure it's working as intended before it goes live, eh?