As I have mentioned before, I have never been a fan of memetics: it always struck me as a potentially interesting redescription, but not as a genuine causal theory of culture. I don't think I hate it as much as Greg from Neuroanthropology, though. He thinks memetics "is nonsense on stilts on skates on thin ice on borrowed time (apologies to Bentham), as deserving of the designation ’science’ as astrology, phrenology, or economic forecasting." And he has 10 reasons (including one drawn from yours truly) to back up his position: check out his article.
I do think Greg takes it a bit too far occasionally. Poisoning the well with respect to Susan Blackmore isn't fair and I don't think she's as bad as Greg lets on (when she's not waffling about memetics). She came across as perfectly sensible when she was interviewed on Point of Inquiry, for example. That said, memetics deserves all the flak it gets.
(Hat tip: Simon Halliday)