In reasonably short order we were standing inside the Ulduar instance taking in the scenery. The beginning of the instance is all vehicles and destroying towers and good, good fun. I was piloting a Demolisher with Ellevis riding shot-gun, I suspect much to his chagrin as I have little sense of direction. In my defense however when there are four possible directions to go, "Go that way!!" is not very helpful. :) After clearing all the trash and getting used to our vehicles, we engaged the boss, Flame Leviathon. Well, technically we engaged a bunch of large brutes in front a door, and after we beat them down the boss crashed through said door and engaged us. After a few tries and figuring out stuff, we managed to down our first boss in Ulduar !!
After that we moved on and wiped several times to the trash in front of Ignis, and wiped 3 times to Razorscale. It was awesome to not actually breeze through content, and to have to think and play well to succeed (hope I can remember how.)
After the raid broke up, I went and checked out the Argent Tournament. There doesn't seem to be too much to it, but it is designed to get more in depth as you go on, needing three days of dailies to advance to the next phase. I didn't try to joust another person which I suspect will be more interesting.
I will give more impressions as I am able to play more, but I am very optimistic about the raiding.