my iphone 4 arrived earlier this week. i haven't experienced any signal problems yet. but that could just be because i've only been in places with good AT&T signal strength. i was planning to buy a bumper or case for it later this week, partly to protect the phone when i inevitably drop it but also because the bumper solves the signal problem.
but now i think i'm going to wait, at least for a few more days. apple is getting mercilessly panned for its signal design flaw. while apple initially claimed the signal loss was a software problem and not a design flaw, its software fix doesn't solve the problem.
so apple is holding a press conference on friday. if they're smart, they'll give all iphone users a free bumper. and that's why i'll wait a few more days before i buy one.