All they naysayers forget app lock-in...
People are not dumb, but they may be locked-in to buying an iPhone 4 if they have an old iPhone and have hundreds of dollars of iOS apps they they have already purchased. I mean, which is worse to my pocketbook - re-purchasing all of my apps on Android , or simply putting a case on the iPhone 4? Given that I have Navionics marine charting, TomTom, OmniFocus, QuickOffice, and a host of games and other utility apps on iOS, I'm thinking that a case is a whole lot cheaper than to re-buy them all.
For many sane, rational people, they will figure that an iPhone 4 and a case is a whole lot less of a problem (and less expensive!) than re-buying all their apps, converting their music and changing players, etc. It's not about the technology, it's not about how good or bad a person Steve Jobs is...it's simply what costs less and is less of a problem if you happen to already own an iPhone but need a new one.
And my guess is, a whole lot of people that fit in that category.
Let the downvoting begin...lol...