In theory this attempt to make influence a fungible commodity seems like a novel effort. If you're a well-respected expert on, say, VMware, but want to promote your sister-in-law's new novel, a "whuffie" marketplace allows you to make that trade. Or you may just want to expand your blog readership beyond the circles you can already reach.
But, I remain dubious. It seems like the desire to do any sort of cross-domain "credibility swap" would be rare. It's hard to see how a Duncan Epping would be motivated to earn points by making tweets he wouldn't otherwise send. But there's no economy of influence without those additional tweets, so there has to be a critical mass of influencers who think they could be bigger influencers--- or, enough people who wouldn't otherwise see each others' content but do have Chasm.io in common.