C# is a lot different today than it was 7 years ago. You might be in for a shock. The nice thing is you can develop it today as you did 7 years ago, but with heavy use of lambdas and var, it reads almost like another language.
7 years ago was 2009. var, lambdas, and linq were already in pretty heavy use by then. The biggest change since then is the dynamic language runtime, but I don't really see that used much in c#.