I strongly disagree with placing Minecraft as the #1 Rift experience. In Half-Life 2, aiming and looking are entirely discrete but in Minecrift (Rift extension for Minecraft), looking and aiming are bound together and you can't even aim upwards (mouse/hydra control is limited to horizontal movement only) to mine tree blocks directly above you without looking 90° straight up and having your headphones fall off.
It's not game-breakingly-bad, but it surely is bad enough that I wouldn't even mention Minecraft in the top 5.
I've tried several demos, and Minecrift has been the only one I've gone back to several times. When I tried HL2, there were perspective and latency issues to the point that I couldn't play for more than 15 minutes.
Yeah, they've fixed some issues in the tf2 rift mode that haven't been moved over to the hl2 build yet. In the forums they mentioned that they should be coming soon.
Turn on pitch as well for mouse aim, I find that the optimal translation of 2d mouse look/aim with the ability to still use your head to look around what you're aiming at - just like a 2d monitor, but now it's 3d - woah.
It's not game-breakingly-bad, but it surely is bad enough that I wouldn't even mention Minecraft in the top 5.