I've personally experienced that, even with extremely minor integration. I wanted for people to "like" my blog posts on my scratch-built blog. There had been an outstanding style issue with their buttons a year before I implemented it. Finally, after my last round of trying to fix it(after having my blog just look subpar for 2 years), I checked the bug. Apparently they "fixed" it, followed by tons of people commenting and say nothing was changed.

So, I switched to twitter "tweet" buttons. Integration took my about 30 minutes. No style issues either. I'm not saying I trust Twitter more, they've had some crap API problems recently as well... but I'm just saying I don't trust Facebook, not for a second.