Microsoft is still busy working on push-email for Windows Mobile 5, but they've found the time (and engineers) to develop its successor, code-named "Crossbow". In order to catch up feature-wise to the Blackberry, the new version is going to include built-in IM and Office 2007 compatibility.

By removing the external dependency on the Blackberry software, an enterprise with 20,000 mobile users could save up to $1.5 million just from licensing. It normally takes from 6 to 12 months for mobile operators to test a new OS, so you won't be seeing this until sometime in '07.

Microsoft Developing Next Mobile OS: Crossbow [PC World]

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