It would be cool if it also allowed one off donations. I live and earn in a country, where "a [US-priced] coffee cup monthly" is a tad too much for me to accept in budget; but I've just recently donated for the first time to an OSS project, and was very happy about this. I imagine that such a obe-off could become a kind of "gateway drug" to slowly increase the spending, and maybe at some point get accustomed enough so that I could even become a recurring payer.
Also, please try to support PayPal, bad/evil as it is. Credit cards aren't a thing everywhere in the world.
Hm. You actually made me look at it, and it indeed does look interesting. Somehow, I always had an unfavourable impression about BountySource before; now that I think of it, possibly because of clunky GUI? Or, I believe it may be that the "capturing/overlaying" of GitHub Issues they do feels uncannily scammy to me?
Edit: don't fully understand it, but somehow I have a feeling it'd help me if I saw people behind the project emphasized more? I now remember I also supported the Voxel Quest author (Gavan Woolery) via his project. The "regular" (non-Kickstarter) one however was Calibre.
Also, please try to support PayPal, bad/evil as it is. Credit cards aren't a thing everywhere in the world.