Since I started shooting digital, one of the things that seems to continually plague Canon is the support and lack of support for viewing raw files in the windows OS. MS has previously released codecs that provide support specifically for Canon raw files, but these codecs do not always work in newer systems.
Enter FastPictureViewer and their codecs providing raw file support in Windows OS's, including Win 7 64-bit.
If you want to be able to see your raw images quickly in windows explorer, windows photo viewer and windows media center, these codecs will let you do that.
I'm still checking out their "Pro" version and trying to determine if it will benefit my workflow or not, but I'm happy to see raw file thumbnails again.
These codecs support a large number of raw file types.