The Blackberry used to be the email weapon of choice for its instantaneous "push" email capability. Now Google is bringing that same rapid delivery to iPhone and Windows Mobile devices with its Gmail service, putting Blackberry's enterprise rule in potential jeopardy. If you've ever harassed your IT department to swap your Blackberry for an iPhone, this should give you more ammunition.

Google's always-on connection, called Google Sync, has been allowing quick syncing of contacts and calendars to these devices for months. But by adding Gmail to the array makes Google's enterprise-level Apps suite an even more tempting alternative to Microsoft Exchange and Lotus Notes. For employees who are sick of being tied to a Blackberry, that switch gives them a choice of alternative devices.

How does it work? Google Sync now allows you to set up your Gmail account as an Exchange account in Apple Mail, mimicing the always-on service Exchange is great for. And since Mail can run in the background of the phone, messages stream in constantly. To see Google's tutorial for non-enterprise users, click here.