Re: If it's not currency, where's the incentive to mine blocks?
What a blockchain is (and the key is in the word itself) is a running ledger in which each new entry authenticates the stuff before it, and so on back. I suppose the book equivalent is to only use indelible ink on tear-resistant pages (both provide tamper-evidence similar to the signatures on the blockchain entries). But at least a blockchain is pretty easy to duplicate while preserving whatever authenticity it provides.
I've been leery of articles that discuss blockchains as well, but I at least take the view of, "Why do you need to keep a running book of authenticated transactions?" It's just that everything I've seen so far apart from e-currencies lack that need, so I move on. There's probably some legitimate uses out there that I haven't seen yet (using a blockchain in a courier or delivery service, for example); it's just we're still at the "90% hype" stage.