As Microsoft and IBM battle each other in the enterprise messaging and collaboration market, Google is moving aggressively to convert users of Exchange and Lotus Notes to Google Apps.

Last month, Google introduced Google Apps Sync for Microsoft Outlook, client-side software that allows Outlook users to trade their Exchange server for the Google Apps cloud.

And on Tuesday, Google rolled out Google Apps Migration for Lotus Notes, a native Notes application to help move e-mail, contacts, and calendar data from Notes to Google Apps. The tool is available to Google Apps Premier or Education users as a free download.

Chris Vander Mey, senior product manager for Google Enterprise, says Google has been working to enhance its online applications by lowering the barriers to enterprise adoption.

"With the tools we're announcing today, we can bring radically lower cost to Lotus Notes users and make it easy for them to switch to the cloud," he said.

There's no shortage of candidates for conversion: At the Lotusphere conference in January, IBM said that the number of Notes licenses had reached 145 million worldwide. Google estimates that 17% of the business e-mail market uses Lotus Notes.

Google, a relative newcomer to the enterprise market, claims to have 1.75 million businesses using Google Apps.

JohnsonDiversey recently migrated 10,000 of its employees from Notes to Google Apps.

In a video, CIO Brent Hoag expresses his enthusiasm for Google Apps, noting that back when his company used Notes and Exchange, a common complaint from users was that they were frequently exceeding their 200 MB e-mail storage allotment.

Other recent converts to Google's cloud include Fairchild Semiconductor and Hamilton Beach. Google claims that Fairchild Semiconductor will save $500,000 annually as a result of its move to Google Apps.

Google is also introducing Google Calendar Labs, a proving ground for optional, experimental features that's accessible through the Labs tab under Calendar's Settings menu. Six new Calendar features are included: Next Meeting, Background Image, Attach Google Docs, Free or Busy, World Clock, and Jump to Date. Calendar Labs may not be immediately available to all users, as per Google's typical staggered service roll-out.

With Google Calendar Labs comes a change in Google Calendar that makes it a gadget container. This means Google Gadgets can interact with Calendar data and developers can create their own Calendar gadgets using the new Calendar API.

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