Everyone seems to agree that you need to bet more in this situation... but can you get away from it on the river in this situation? A large portion of your 100BB stack will be committed already. 4BB preflop, ~10BB on flop, 30BB on turn... a little less than half your stack is in now. With the things that most people said here, they'd fold to a river push, even with ~45% of their stack already in (maybe not a bad idea). But if good players pick up on this, it seems to me that we'll be getting moved off a lot of pots since we're not loose.

...just playing devil's advocate, of course.