Wasn't Flex a better alternative to ExtJS in this problem-space? Recently I've seen entire apps packaged up as Silverlight, which seems to work well - especial

Wasn't Flex a better alternative to ExtJS in this problem-space? Recently I've seen entire apps packaged up as Silverlight, which seems to work well - especially where security (exam marking in this case) is important. Not sure how they're built mind, and it took an age to download, but for intranets it's another interesting approach.