When I first set up my Gmail IMAP, "all mail" and inbox were both telling me I had new mail like many of you are saying, and it was indeed annoying. Sometime yesterday however, it stopped doing that, and now only my inbox shows new mail. I didn't change any setting on the Gmail side or Apple Mail side... Weird, but works for me. Maybe Google changed something on their end? Has anyone else observed this?
Other than that, Apple Mail has been unable to access any of my IMAP Gmail accounts (I have 4 of them) for the last couple hours or so... They're fine through Safari, though.
Is there a way to unsubscribe from "All Mail" in Leopard Mail? I'm on Tiger, so I can't test.