I'm having the same issue. Tried deleting the MobileMe account and adding it back in. It seems as though the sync from my Macbook Pro to MM is fine, as the contacts on the site are editing. The push from Apple to iOS devices is what seems to be down, as neither my iPad or iPhone are populating my contacts.
I may just leave it until tomorrow AM to see if Apple takes care of it. Don't really want to deal with the MM tech support.