Microsoft IronPython is a codename of the early pre-alpha release of the new Implementation Running on .NET of Python programming language. It supports an interactive interpreter with fully dynamic compilation. It is well integrated with the rest of the framework and makes all .NET libraries easily available to Python programmers.
Microsoft advises that this program is only suitable for experimentation purposes and not serious development work. If you are worried about stability and funtionality it is advised that you wait for a more stable version to be released or until the first beta is released.