Two other music bundles were mentioned by their creators on the reddit thread:
http://musicrage.org/ http://indie-allstars.com/ http://www.reddit.com/r/Music/comments/x74i5/the_humble_musi...
http://musicrage.org/ http://indie-allstars.com/ http://www.reddit.com/r/Music/comments/x74i5/the_humble_musi...
The difference is that bundle had a ton of albums whereas here it's only a handful. I expected also to see a more game-centric flavour to the soundtracks -- considering the pedigree of the Humble Bundle -- instead of stuff like They Might be Giants.