I deleted all three peers in the connections pane and the "it appears your machine . . . . is disconnected" dialog popped up. I was still connected.

I tried again, but couldn't repeat (because of incoming search results?)

Tried again with no tranfers in progress, but FW switched to Ultrapeer. heh.

Anyway, would a check that pings "the internet" before showing the "disconnected" message prevent at least one case of a false trigger?