What you should know about the Roslyn compiler at this point?

What is the Roslyn compiler? Shortly put, it is the next version of the C# compiler that exposes it's inner workings inside out. For instance, developers get access to the parser, lexical analysis and optimization stages, and able to build tools that take advantage of this new information.

At this stage, the Roslyn compiler is available as a CTP version. Note that in addition to supporting the C# language, the Roslyn project actually does the same opening of compiler internals for the Visual Basic language?

If you are interested in further details, there's a good white paper available for you to read.