Almost a year ago, Google announced the Gmail API. Today, they're adding push notification support, meaning you no longer have to poll Gmail constantly for new messages if you're a developer or service utilizing that API, which is going to make the 3rd party Gmail app experience much better.
If you want to know about implementation, you can read about it on the Google developers site here, and it sounds like it's going to be a pretty simple switch.
Gmail offers both IMAP and its own native API for use by third-party developers, but only the official Gmail API supports features like threaded replies, drafts, specific permissions, native search, and more. With push here, it's basically the only way to go unless your organization refuses to let you use anything but IMAP.
- Google Apps Developer Blog