I have to admit that I largely ignore indie games, unless they're on the XBL indie service. Why? 1) because I'm too lazy to seek them out, and 2) because I like to have all my games in one place (as mentioned in an earlier post) Also, it can be a bitch to hear about/keep up with new indie games, because they don't always get noticed.
On the PC, I use Steam for everything out of convenience. For non-Steam games, I put a shortcut in Steam. I like the XBL indie channel because games update automatically, and I can easily just glance over the new releases on a regular basis and rarely miss something. Also the games are all designed with a controller in mind, which is not always the case with PC indie games. For example I was messing around with
Gish and
Jumper Three last night. (I don't know if the guy that made Jumper is on the Super Meat Boy team, or influenced them, but it's overwhelmingly similar) I was having issues with my gamepad (Xbox controller)
I have Gish from the Humble Bundle, which is version 1.53. Current version is 1.6, and there's no way to update unless you bought through the game's website (You're SOL if you got it from the Humble Bundle or Steam) The game won't recognize my controller. I rebought the game so I could get the newest version, and the problem still exists. I could play with the keyboard, but that just feels really cumbersome.
With Jumper Three, the controller was detected fine. What I didn't like, was that it didn't recognize the d-pad (treated as a hat switch by the PC, I think), and the movement with the analog stick was much more sensitive than with the keyboard. Some jumps were designed so you could just make it across a gap, but I'd fly past it because my movement was different. Super Meat Boy will likely be better than this "slightly more indie" version, just because of being designed for a controller. (also the Meat Boy style and theme song are fuck-awesome)
Also, a note about my controller complaints: most indie games I give a try are 2D platformers (a genre that needs more love). Obviously I wouldn't try to play an indie FPS with a controller.