As a few people have said already, I think it'll slowly become more crap and alternatives will slowly bring in people who get sick of it.
They're hoping for IPO and once that's done, they'll be much less forgiving when it comes to cash grabs. I can imagine them doing things like getting rid of old.reddit, not allowing the hiding of suggested posts, ads which are very targeted and intrusive.
I saw an article on the official Reddit Inc website talking about the use context in advertising, where advertiser's can change their ad based on the context of the thread. It doesn't say how they're implementing this but I could imagine a situation where they put ads directly into threads. Either way you'll start to see ads using wording which mimics the subreddits you're in or the comments you write.
I have the feeling the reddits decisions are just going to get worse as long as they can get away with it.