I have not been able to replicate the signal issue at all in various locations and holding the phone in the way shown in videos. The most a get is one bar drop similar to what a 3GS does, even in areas that are not soo good signal wise.
I actually get a better signal in fringe areas than my 3GS like for like. where the 3GS is going 2G/Edge, the iPhour is still surfing/calling on 3G! The sensor issue during calls has shown it's head a few times but thats it.
Getting great download speeds too, much faster both on the download and obviously upload.
http://i1043.photobucket.com/albums/...zlad/photo.png
Busy Saturday night (Sunday morning), Handheld!
If you really want to see the iPhone 4 die a horrible death look here:
http://www.willitblend.com/videos.as...&video=iphone4
I think it puts up a good battle against that blade!!!!!