Even if your not into .NET development it is still good news for the Ruby world that Microsoft is creating a DLR called IronRuby.
You may recognise this as there is already IronPython and I would think a whole host of new implementations now that DLR has gone open source.
So there are now lots of choices to develop Ruby solutions, from TextMate to Netbeans and now Visual Studio.
This is great for the future of Ruby and the Rails framework.