Incidentally, I saw the silicone case today, but Best Buy only received one, and a person who arrived after me got it because the clerk helped them first.

I have been using silicone cases on my iPods and on my Zune for years, and they tend to be quite smug and great protection. I prefer them over the hard cases because they seem to be less bulky and the fact it gives a bit when dropped makes me think it's possibly better in case the phone gets dropped.