Re: The chicken and the egg
You mean no tactility except the positional banding (which is up for change depending on what beta testers say - may gets some nubs/depressions to compensate for lack of a d-pad) and the ultra high resolution haptic feedback (the highest bandwidth, and as such, variance of feedback, available on any consumer device as far as Valve are aware) which those who have used it have said works quite well, depending on the sort of game you are playing.
You know, like Tommy Refenes, designer of Super Meat Boy:
http://tommyrefenes.tumblr.com/post/62476523677/my-time-with-the-steam-controller
Generally positive for what (at the time) would be alpha hardware, and is now moving into beta, with lots more testing to come - and feedback. Lots of feedback.
I'd expect more on this next month when (presumably) the beta units start rolling out.
And for reference, you can use your keyboard and mouse, your XBox wired controller, or anything else that works on your PC with SteamOS as far as Steam are concerned - but they need joypad testers for the beta - hence the requirement of beta testers to have a joypad installed and configured under their Steam config.
They need to test the primary market - the rest of us, should we go for SteamOS, can do what we want.
I'll happily stick with a keyboard and mouse for FPS, but these controllers do look very interesting indeed....
Steven R