It's going to grow hugely (at least as long as punters keep using bitcoin); there's an expectation that clients will switch away from using the full history sooner or later, and there are mechanisms prepared for remaining reasonably secure with shorter histories.

Hah, so eventually only a few people like central power figures in the bitcoin community will be running with the full blockchain eh? Probably my favorite thing about bitcoin is how, despite its explicit goals, the more adoption it sees the more it looks like it will turn into the same old thing we already have.

I remember a friend making a similar comment about EVE online: you set people loose in this anarchistic, libertarian blank state, give them a few years, and... turns out they'll band together into gangs with leaders, that develop into communities with formal governance processes; neighbours helping each other out grows into insurance syndicates....

We've already seen people wanting an authority to compensate them when their bitcoins are stolen; bitcoins are meant to behave like cash, but an FDICed bank account is much more useful than cash for most people. That said, as long as the full feed remains open to anyone who has the spare compute power/disk space and wants to connect up to it, there's still a big difference from the existing financial system.

That's not even a large portion of the blockchain anymore. The full thing is 7GB now, and most of the large transactions are in the very recent bit.