I was astonished when I first visited chainBB as thinking it was a totally different cryptographic blockchain but the I realized it was using Steem's blockchain. It's indeed pretty awesome.

As for the incentive part being brought up by jestus, it seems pretty fair as also they need to somehow raise for themselves as well. As to the 15%, I think this will change drastically according the Steem's price valuation.

I'm also looking forward with the possible new features in the coming weeks. :)