Long ago, long before I knew anything about anything relating to bikes (one could question whether I know anything right now, actually), I rode a pair of Dura-Ace tubeless wheels.
They were the 7801-SL version, and I took advantage of a RAGBRAI demo to give them a shot. I was pretty much hooked instantly. Fast and stiff and light. And smooth — so, so smooth.
Fast forward to the winter, when I bought a slightly used pair from a teammate. I set them up tubeless and raced them the next summer and into 2009. One wheel was destroyed in the Lincoln crash, while the other remained unscathed (it now serves as a training wheel).
I spent the rest of 2009 and all of this season on standard clinchers. They were just fine, but I really like road tubeless.
My current bike has Dura-Ace tubeless wheels once again — the 7850 C24 TU model. It's fast and smooth and light. And there are more tire choices available each season. They're loaded with Caffe Latex (but no glitter, Rafal) and have the Bontrager R4 tubeless tire (aka the Hutchinson Atom).
My stance: Road tubeless is going to be huge within two years. It makes too much sense not to be.
Your stance: In the comments. Go!