My one concern is the lack of thumb sticks as well. Who knows maybe the tech will work, and Steam will put some magic into it that nobody else can, but thumb sticks are a known item that works pretty well for what they are designed for.
I think of the Xbox 360 controller as the perfect controller. Every button is easy to use, easy to reach, easy to notice when you push said buttons.
I've been kind of wondering if the gaming industry would ever give up on thumb-sticks and start using game pads like this. I've had a history of breaking the thumb sticks on my PS2 controllers and I've halfway broke my left PS3 thumbstick already, it gets stuck sometimes when pushing to the right and it rotates in place for some reason. It's the most common reason aside from cord problems that controllers become broken, and I think Valve has turned things around. Not to mention how hackable and redesignable these things will be, I imagine they'll be pretty sturdy at that.
I think concave thumbpads are perfect and I believe they'll be more sensitive also. You know what else is genius? Having the XY,AB buttons RIGHT next to the thumbpads so you barely have to take your hand off the movement controls to perform another action, while the remaining buttons are on the back of the controller. Like they said you hardly have to lift a finger to do anything, aside from press start or one of the other keys binded to the center pad.
You can use a mouse and keyboard right along with it too. The controller won't be too useful to anti-controller fanatics, or FPS only gamers but maybe having the Steambox out there will cause developers to make games for the Box along with PS4,XB1 and WiiU and in that sense the controller becomes a necessity. There are all sorts of racing games, arcade shooters, indie games and the such that will work amazing on a controller like this, and on top of that you'll be able to bind it however the hell you want? How could you not like it?
OHH I WAS MOLESTED BY A TOUCHPAD ONCE, IT TOUCHED ME IN MY NAUGHTY SPOT AND EVER SINCE IVE HATED THEM. Just the way they feel sends shivers down my spine. It's completely impossible that anyone could ever properly design a controller in a useful fashion, so useful in fact they chose it over controller sticks or D-pads; especially Valve, if anyone could do it it's definitely not Valve, they clearly fucked up and failed to make the observations we have. Guess we're going to have to use our PS3/XB/computer controllers instead. :/
I'm seriously excited for this controller though, as I knew the Steambox was going to have an accompanying controller and this is far more than what I expected. I really thought they were going to throw out a Dualshock knockoff or something so this makes me really happy. It's original and it looks sexy. Sure not all games will work well with it but like I said you can run a keyboard with it or not use it at all. This is opening the Valve market to millions of new users. I get not wanting to play with controllers but there's no real reason to dislike it as far as I can see.