As you probably noticed, the Windows 7 Release Candidate is officially available on TechNet/MSDN and will be available to the general public on 5/5. The Windows 7 Engineering blog has a post about the new personalization features available in the RC:

In developing the personalization features, we knew that we wanted great content for people to express their personal style. Because the desktop background is such a vibrant surface, we wanted to focus on providing quality content that demonstrated how creative people could be with this feature. When folks send us screenshots using the feedback button, we are regularly inspired by the rich diversity and personality of the wallpapers that people choose.

As we thought about how we wanted to approach personalization in Windows 7, we knew one way was to honor our lineage. In the past photography has been featured heavily Windows. Some of that photography has been quite beautiful and has become a proud tradition we wanted to maintain. In addition, we also wanted to explore new territory and expand our visual palette. In the realm of photography, we kept a theme focused on landscape photography which is our tradition, but added new themes for architecture and nature. Much of the this imagery is from our stock imagery partners, but we also had the good fortune to work with a talented local photographer named Will Austin, who has photographed all over the world on many subjects with an emphasis on architecture. Will's photos provide a little bit of the local flavor of the Seattle area that we are proud to call home.