drawLogic has a roundup of 5 Good, Usable rich internet applications done in Flex and Silverlight. A good summary of some really well built apps! If you are interested in RIA’s, you should check them out!
And if you can’t wait to go try them out, here are the 4 I like:
The topic of Ryan Christensen’s blog entry essentially is usability in RIAs. He says you can use any technology, but what really matters is the usability of the application! Valid point Ryan!