I knew that MSDN Library is a great tool to learn, but I underestimated it until now that I found myself that I cannot acquire any good book about new technologies such as WPF from .NET 3.0 (as there are no such books yet pirnted!)
Yes, I need to learn WPF to work on a new internal project at the company, and the way MSDN Library presents the technology is in my opinion, awesome. Regarding WPF, I found MSDN more attractive than Google-found sites, really!
For everyone interested, here is a really nice start for learning about the WPF architecture (and not blah-blah about creating 2 buttons with a nice look and event responsiveness :-)): http://msdn2.microsoft.com/en-us/library/ms750441.aspx. Then follow the good links and read other awesome articles.