After the Marc Hauser case last year, it might have been reasonable to think that we wouldn't see another scandal hit psychology for a while (although it'd be a slightly better bet that the Hauser story wasn't finished yet).
Alas, that hasn't turned out to be the case, as a highly cited Dutch psychologist - Diederik Stapel - has been found outright falsifying the data for at least thirty papers (some of which were published in journals as highly regarded as Science). What does this mean for social psychology? I don't know; it's not my field, and the Nature article I linked to above quotes Oxford psychologist Miles Hewstone as suggesting that Stapel's work wasn't actually that influential. So the tentative response is; not much.
I can't say I'm optimistic about the effect it will have on the reputation of psychology as a whole, though. The field really needs to figure out some way to improve its public relations; a case in point is this article, which implicitly suggests that both the recent fraud cases and the sheer number of criticisms from within the field threaten to disrupt the "fragile respectability" that psychology has only "recently" earned. Whether that's the case or not, it's pretty clear that psychology desperately needs to improve its image.