So IronRuby has been released in a pre-alpha state... check out the comments on John Lam's post for some additional details not in the post itself.

c:devresourcesIronRuby-Pre-Alpha1BinRelease>rbx.exe

IronRuby Pre-Alpha (1.0.0.0) on .NET 2.0.50727.312

Copyright (c) Microsoft Corporation. All rights reserved.

>>> class RubyAlpha

...     def hello

...            puts "Hello"

...        end

... end

=> nil

>>> r = RubyAlpha.new()

=> #

>>> r.hello

Hello

=> nil

>>>

Things of interest:

• Lots of stuff doesn't work just yet ;o)
  
• it will end up on Rubyforge, not Codeplex... and I think it's quite an appropriate decision considering the nature of the project... good to see common sense winning over marketing dogma - and it's going to be there by the end of August.
  
  
• The project will eventually be entirely open to community contributions (I don't think that includes the code making up the DLR itself, as a shared platform that's probably something that needs to be tightly controlled)