Which Version of Python?

[Charles Hottel]

 I have a lot of programming experience in many different languages and now 
I want to learn Python.  Which version do you suggest I download, Python 2.x 
or Python 3.x ?  Also why should I prefer one over the other?

Right now I am thinkng Python 3.x as it has been out since 2008, but I have 
some concerns about backward compatibility with older packages that I might 
want to use.

Thanks for your ideas and help.