Microsoft has released an upgrade to Office Mobile 2010 in conjunction with the release of Office 2010. Office Mobile 2010 has been available for Windows Mobile 6.5 devices in beta form since last year. This new version is a free upgrade and is available in the Windows Marketplace. Note that your phone must already have a version of Office Mobile installed to use this upgrade, but that should cover most everyone.
This new version of Office Mobile supports the following features as explained in the Microsoft press release:
Effective today, Office Mobile 2010 will be available for free via Windows® Phone Marketplace for all Windows Mobile 6.5 phones with a previous version of Office Mobile. People using Office Mobile 2010 can perform lightweight editing of Office documents and take notes on the go. With Office Mobile, people can work with Office documents stored on their phone, attached to an e-mail, and can browse, edit, and update documents stored on a Microsoft SharePoint 2010 site. SharePoint intranet sites and communities also help people collaborate, regardless of location.
Related research on GigaOM Pro (sub. req’d): To Win In the Mobile Market, Focus On Consumers