IronPython 2.0 Alpha 7 is now available:

IronPython 2.0 Alpha 7 (source and binary) is now available:
IronPython Project Homepage
Release Notes and Download

There’s been numerous changes to IronPython in the past month and a half. Most notably a lot of work has been done to get usage of the ‘yield’ statement compatible with CPython 2.5. There might be a few more changes that need to be made, but by and far IP now adheres to PEP 342. Another notable change brings the code closer to the new hosting API spec they published on the mailing list. The next couple of releases should finish that work.