+1 to Google for delivering what the public asked, IMAP support for Gmail. This is especially awesome for us iPhone users, trying to use pop3 for gmail was just not an option on the iphone.

Head into your settings and see if you have an option to enable IMAP, if not just be patient and try again later.

Google has put up a FAQ for IMAP that should answer all your questions.

They did miss a few settings to properly setup the MobileMail.app on the iPhone, instead of typing it all out I’ll redirect you to someone who has already taken the time to right up a good set of instructions.