I was out getting a hair cut, and right before my eyes all my contacts disappeared from my iPhone. All that was left were my favorites, as numbers only. It was just like what happened to my wife's iPhone.
Then, just as mysteriously, my contacts reappeared about 10 secs. later. Then I changed a contact on my phone, including taking and adding a picture. I lost it. MobileMe pushed the original contact info back to my phone instead of syncing the update.
MobileMe push and sync is screwed up today. I'm turning it off.