londrum - 8:29 pm on Sep 6, 2011 (gmt 0)
maybe you are right. but ive now recovered totally -- a week and a half after moving to a dedicated server.
i made no changes to the site otherwise. all i did was improve my page speed by moving away from shared hosting.
if it wasn't page speed then it must be something to do with bounce rate. either way, i didn't realise that either of those things had such a dramatic impact on your rankings. my traffic was cut in half overnight.