What's wrong about backward compatibility. When MS had to make lots of changes to .NET 2.0 and broke pretty much every application that was implemented for .NET 1.0 that was a major turn off, so many people found another excuse dismissing MS. So if MS aren't backward compatibility that's bad, but if Python that's good?

Dead languages are actually good, you can extend them while keeping the core stable and extending them with other flavours (e.g. J2ME, Android, JSP) making them easy be adopted to new uses.

BTW Delphi is the most backward compatibility language that I know,