Saying that "all smartphones" suffers from antenna issues is a total crutch.
Fact is they may, however they shouldn't. Instead of striving to make a perfect device Apple and almost all other tech companies just try to make something better then the norm. Then giving us reasons to settle, instead of fixing the problem. Not at all happy with todays conference. Still not wanting an iPhone4
Your statement that they shouldn't suffer antenna issues is counter to the laws of physics. However, the iPhone does suffer a secondary antenna issue that could have been prevented.
If you look at how an antenna works, it acts by attenuating the electrical signal caused by electron stimulation due to impacting photons in a metal rod of fixed length. The length of the rod directly correlates to which frequency/wavelength of photons are most optimal for this electron stimulation. There are two items that principally affect signal strength on any antenna:
1. Modification of the conductive length of the antenna. This directly affects the frequency response of the antenna, causing the wavelength that results in optimal gain to change. This can be caused by a physical contact between the hand and the antenna without sufficient insulated separation.
2. The effect of the hand on interfering with signal transmission due to effects similar to that of a Faraday Cage (see
http://en.wikipedia.org/wiki/Faraday_cage). This issue affects all cell phones that are held, but is more prone to affect those phones with antennas that cover a smaller physical area (such as phones that use fractal antennas, which is most phones).
In Apple's demo, only the iPhone is especially susceptible to 1.This is because the iPhone has an uninsulated external antenna, and in fact, has multiple antennas that can have the gap bridged by the conductive surface of a human hand, causing a significant change in the frequency of optimal gain.
All cell phones are susceptible to 2, though the iPhone less so due to it's larger antenna. This is because most cell phones actually use a fractal antenna to reduce size, placing it inside the phone. Fractal antennas are generally very small, often smaller than the tip of a human finger. Apple's solution, while making 1 a significant issue, actually helps reduce the Faraday Cage issue by utilizing a much larger antenna, which in turn is harder to block in the normal process of gripping a phone. So while mitigating one issue, they caused another issue.
Apple's solution (free cases, free bumpers) should solve the issue from the standpoint that they add an insulation layer between the conductive antenna and the hand, preventing a change in the frequency of optimal gain, and limiting the issue only to affect 2 above.
This is a design flaw (the antenna should have been insulated) but it is an easy fix with a bumper.