There are a new series of paypal scam e-mails making the rounds. I almost got snagged by the first one; it was just dumb luck that those thieves didn't make their "home" site look enough like paypal's. The second one I got I had fun with, telling them all sorts of hokey stuff.
At any rate, if you receive any e-mail notices about paypal irregularities, strange activity, security confirmation, etc., no matter how legitimate it looks just discard them. If you're a little worried (I was), go visit paypal directly (type in the URL by hand) and check your account.
Under no circumstances should you ever give your account info out because of an e-mail notice of any kind, no matter how legitimate it may look