Ugh. I'm going through the same thing right now. Management wants everything "web-based" and they don'y really have a good reason. They assume everything can be done on the web and that is completely untrue. You lose so much richness when you move to straight server-side. Add to that the fact that your entire programming team will probably have to do an insane learning curve if they don't have this knowledge already. Bah. Guess I'm just venting.

For example: I work with clinical systems in a hospital. Do i want to post patient information up on a website even if it is a "secure" intranet? Gawd no. And websites (even Microsoft itself) get hacked everyday. There is no way I am going to risk that without a damned good reason as to why it should be purely web-based. I'm sure you'll here other examples but to me security is a BIG one.