Funny you should ask! I was just wondering this myself, last night. To find out, I decided to run them side-by-side with the same gmail account installed, both as push mail. The gmail app works extremely well, and I get notifications instantly, but I wanted the extended functionality of the mail app. I will post back in a day or so whether the mail app gets notifications as quickly as the gmail app, which was my primary concern. Coming from WinMo, i can tell you that the exchange connectivity to Google can be a PITA. I hope the big G gives preference to their own operating system! Either way, the mail app has more desktop-email-clienty features, like copy and paste from messages, and the gmail app has more gmail-specific features, like label-handling and stars. Otherwise, it's just a matter of preference. Neither is perfect. i may end up running both, one as push mail and one set to manually check mail, if I need the features.