Say you are having a hardware related issue on your iPhone, first place you would think to go is your local Apple store, right? Well not if you're running iPhone 3.0 Beta it turns out, as MacRumors forums show you will politely get rejected and denied sort of help.
TiPb has confirmed this is indeed true from speaking with a few Apple employees.
Now where does that leave someone who purchased the beta from a stranger on Graigslist? Not in a good place obviously since to get your issue taken care of or to have your phone replaced you must call a developer-only help line. Now if you are a bit more expierienced with the iPhone you can always try to downgrade back to the 2.2.1 software before going into the Apple Store but say your home button is not working, you are flat out of luck and you are now stuck with a official iPhone paper weight.
So with all that said, TiPb can not stress enough -- and we've said it many times -- do not purchase the 3.0 Beta from anyone.
This late into the beta cycle, in a few short months it will be released to the public anyway.