On the signal loss thing, the guys at Gizmodo might have had their other hand earthed out to a ground plane or something!
Wouldn't put it past them!
But Apple coming up with their Bumpers all of a sudden does tend to suggest that they knew about this issue. Be it a major issue, or a non-issue.
Expect a glib email from Steve Jobs, replying to a rabid fanboy, saying...
"Well buy a Bumper then. Educate yourself about radio signals dude.
Steve.
Sent from my iPhone4 with a Bumper."
... any minute now.