I'm only half joking :) Gitcoin is much looser than bitcoin when it comes to verifying proof of work. However, there is a (practical) sense in which it exists. Fixes are submitted, accepted, merged, pulled until they are part of all users' "blockchains". gitcoin is the quantization of this karma. The lack of a hard definition of work means that it is perhaps easier to bootstrap in a centralized ecosystem like Github. Like Quora credits for code.

In much the same way as Quora credits are used to power A2As, gitcoin would enable you to ask J Random Coder on github for a fix and pay him in karma. The GPL is effectively a no-freeloaders mechanism, gitcoin could be another.