Microsoft Expression Studio is available for download, the trial version for 60days is available here http://www.microsoft.com/expression/.
One of the best features about it is that it doesn't uninstall previous versions of expression studio, so for example if you have expression studio 2 (like me, a free full edition MSDN AA :p) and you want to see the new features in ES3 then you don't have to uninstall anything and there is no compatibility issues also.
There are a lot of new features in this edition that we may discover after but the best one I'll talk about now is Expression Web 3 SuperPreview, it allows you to debug your website on different browsers and different version (IE6, 7, 8, Firefox, Safari) but in the same application, so if you like a lot of other developers and designers who did spent days trying to figure out why is that working on a browser and not on another, then you have just found the best tool that suit your needs.
The following video shows a quick view of how it looks like using Expression Web 3 SuperPreview:
another cool feature also that I loved so much is the improved intellisense, in blender it was really very fast and so responsive, so stylish too, since it includes the documentation in the context menu itself as shown in the following video :
You can see the code of bloginto in that video :), it's XAML and it's completely designed in blend, and Expression Blend 3 can even edit C# code and run it directly without the need of visual studio. Well now nothing left, just fire Expression web and get to work.
[Update]
I forgot to mention to show the HTML DOM tree and the size manipulation of the browsers when doing tests as shown in this picture, but yes they are there fully supported.
