Interesting, this is something that would interest a lot of people who have coins just sitting around. A good point mentioned above me is where will the money come for the interest? this will need to be explained before they can be taken seriously as this is a very important point, will sign up for the updates.
I communicated with Jonathan Azeroual, CEO/co-founder at BSave, with many of these questions a few days ago. I wasn't going to join their early beta without something more than what's in their metatags.
He says they are generating income by margin lending. That's a fairly safe investment, as I do that already (because margin traders deserve to have others make money off of their lunacy). I don't yet know what platforms they are lending on. Funds are basically distributed based amount/time invested. Of course BSave takes their cut of the income before distribution. Apparently interest was healthy early this month due to market volatility, but is now around 3%, but projections are near impossible at this stage.
They say they don't have much info online because it's a private beta test and they're looking for first impressions and bug reports by users. (They pay a small bounty reward for bug spotting.)
So I'll be throwing a small amount into the pot and beta test it and call it contributing to the community ... or something.