There are many new things to learn.....
You said that you are a developer hence iam suggesting these topics.
As the design of the front end part is concerned you could refer what is Jquery , Silverlight etc
For getting through some knowledge in the database arena see what is LINQ all about .
You could also work on latest developments on Framework 4.0
Some of the concepts i suggest you to do is ---> Asp.Net State Management , Url Rewritting , Dealing with Cache Memory and Cookies , Deploying a WCF service on IIS , Running a Windows Service......
There are so many new concepts coming it is very tough to update ourselfs , But we have to do.......
Note : The topics i suggested above should be touched only when you are comfortable and strong enough with the Basics .
Thanks,
Radha Srikanth
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