In DetikInet, i saw a news which stated that Microsoft is predicted to start working on Microsoft Office which runs on GNU/Linux platform in the next two years. IMHO, i'm quite agreed with this. Microsoft Office is one of their biggest product and it gaves a lot of revenue to Microsoft. I'm not sure whether they want to make it running on GNU/Linux platform, as they will lose alot of money from Microsoft Office itself.
Besides, Microsoft uses their own proprietary format which limits many people when they want to open other product to open their own files, such as OpenOffice.org even they had created odf-converter to convert between each files. I don't think many people who have used to work with OOo will like this idea, unless Microsoft is willing to use OpenDocument Format as their default format.
Other problem is that Microsoft Office is very close with Windows and it will make interoperability is very hard to be done even with optimized Wine, just like Picasa. You will have an instable product or inconsistent product. But, if Microsoft is willing to do so, then it surely a good news. Let's just wait and see for the next big issue :D