>So far my impression is that unless you are working with .net on a daily basis it is difficult to retain.

That's as true of .NET as it is of anything new you try to learn. I found that while I was reading a lot of .NET books a couple of years ago, it didn't sink in as much as it did when I started working with it every day. Plus, a lot of the books of a few years ago were not very helpful ... they were written using the beta version so some things had changed, which broke a lot of the code samples. Very frustrating. If you were to start now with learning .NET, you'd be well advised to make sure you have fairly recent books.

~~Bonnie