Things are heating up between Google and Microsoft. Google just announced that they are building a platform to migrate Microsoft Exchange users to Google Apps. Google Apps Migration for Microsoft Exchange will copy e-mail, calendar and contact data from an Exchange installation to Google’s Gmail service, a part of Google Apps, preserving folder structures in the process.

From Information Week:

Last summer, Google introduced Google Apps Sync for Microsoft Outlook which allows Outlook users to connect to Google Apps for e-mail, contacts, and calendar data. The company has also released Google Apps Migration for Lotus Notes and Connect for Blackberry Enterprise Server.

Vander Mey said that two large companies have just embarked on the journey to become Google Apps customers, Konica Minolta (7,000 users coming from a mixed IT environment that included Exchange) and National Geographic (2,000 users, migrating from Lotus Notes). Motorola and Jaguar Land Rover, each with 15,000 users, were among the companies last year that left Exchange for Google Apps.

All told, Google claims to have about 25 million individuals and 2 million businesses using Google Apps.

BPOS costs $10 per user per month, or $120 per user per year, more than twice the $50 annual cost for Google Apps. But really, the two services aren’t directly comparable in terms of features. BPOS, for example, doesn’t include Microsoft Office.