Sam Ramji today announced that MS would be investing in the development of SWT on WPF. This is great news for Eclipse and Microsoft for two reasons:
1) Having more resources to work on SWT, especially with the deep knowledge of WPF, will make Eclipse better on Vista. This will allow for tighter integration of Eclipse based products on Vista. This is good news for developers building RCP based applications for Vista and WPF.
2) This definitely shows Microsoft is starting to understand the promise and potential of working with open source. As Sam pointed out today, MS makes money from selling their platform. Open source projects can help sell and add value to the MS platform. If MS supports different open source projects, it is actually good business for Microsoft. Lets hope we see more of this attitude from MS.
This is just the first step. Talk is cheap, so the hard work is to get the right engineers working together to make this happen. Time will tell to see how fast this can happen.
Lets hope next year at EclipseCon, Microsoft will be talking about their plans to extend CDT to support C# and new Eclipse-based tools for Silverlight.
Ian Skerrett 
I first hope they’ll talk about supporting C++ on Windows. C# can happen later.