There is the potential for a major reception issue when you bridge the gap between the two antennas. It doesn't affect everyone obviously. The "uniqueness" comes from the iPhone's design, not the issue of antenna attenuation itself. No other phone has this type of external antenna with that type of gap between two antennas able to be touched as easily. Plenty of other phones will degrade or drop signal given attenuation by touching different elements of the phone specific to their own designs - check the videos on Youtube and Apple's site. For some people this issue will be more prevalent on the iPhone than it would be on their previous phone(s), given its physical design. For others they will be able to get signal where previously they had no signal at all, even if it's not terribly strong. Yet others won't see this problem at all.

That said, Gruber's message was funny as hell.