Updated 5:45 p.m. PDT with more details about e-mail push.
Some of you who have been restlessly awaiting the arrival of Google's official Gmail push solution for mobile phones can relax now. On Tuesday, Google expanded the over-the-air syncing capabilities in its Google Sync service to include Google's e-mail--but only for the iPhone and iPod Touch (version 3.0), and for Windows Mobile phones.
Google Sync began as a beta service to sync Google calendar items and contacts to iPhone, Windows Mobile, and Symbian Series 60 phones. Owners of iPhones, iPod Touches, and Windows Mobile phones can now set it up to include Gmail messages as well.
The phones will receive Google Sync messages through their native e-mail, calendar, and address book apps. Depending on your settings, your phone could vibrate and/or chime to let you know that a new message has come in. Note that Google Sync will not push visual notification boxes to iPhone and iPod Touch interfaces. For that, you'll need third party apps like GPush for iPhone. Instead, it pushes e-mail from the server to the phone, rather than pulls in a list of e-mail messages, a request that the phone's e-mail client makes of the server. Push e-mail is often preferred over "pulled" e-mail for its real-time updates and its lower toll on battery life.
BlackBerry and Nokia Symbian Series 60 users won't have access to pushed Gmail yet, but they can still sync calendar and contact events to the phone's built-in address book and calendar.
To get started, visit m.google.com/sync from your desktop or mobile browser. The step-by-step setup process is best navigated from your computer, and will require you to ultimately configure your phone to sync over the Microsoft Exchange Server.
Related story: Gmail push on iPhone? Meet GPush