[yohoho22]

Looks like they're up around 25% overall, just comparing these two catalog filters that (mostly) exclude DLC:

http://store.steampowered.com/search/?category1=998&os=linux http://store.steampowered.com/search/?category1=998&os=win

2644 games for Linux, and 10750 results for Windows. There's a good deal of high-profile stuff, but Linux support definitely does skew toward the indie side of things.