Just one week shy of Christmas 2008, the Python world saw the release of version 3 of Python. Big deal, eh? Well ... it turns out it was and is, as Python 3 is the first major release of Python designed from the get-go to be incompatible with prior versions of the language.

"Guido just released Python 3.0 alpha 2, to be downloaded at the usual locations -- get it and check it out! ..."

Python 3.0a2 Release: December 7th, 2007
http://www.python.org/download/releases/3.0/

Python 3000 (a.k.a. "Py3k", and released as Python 3.0) is a new version of the language that is incompatible with the 2.x line of releases. The language is mostly the same, but many details, especially how built-in objects like dictionaries and strings work, have changed considerably, and a lot of deprecated features have finally been removed.

The first alpha release of Python 3.0 was made available for download on Friday. Python 3.0 includes syntactic and architectural changes that are incompatible with the 2.x series.

"The 3.0 version of Python (also known as Python3k and Python3000) just got released few hours ago. It's the first ever intentionally backwards-incompatible Python release."

With the latest major Python release, creator Guido van Rossum saw the opportunity to tidy up his famous scripting language. What is different about Python 3.0? In this article, I offer some highlights for Python programmers who are thinking about making the switch to 3.x.

The Python developers have published the first release candidate for Python 2.6.5, addressing nineteen issues in the Python core and over fifty library issues

"This version of my Python mode provides support for the
recently-released Python 3 [...] It's lightly tested; please report problems/deficiencies to me..."

Due to arrive in June 2010, Python 2.7 has now reached its first beta. Python 2.7 is planned to be the last major edition of the Python 2.x series before it goes into "bug fix mode".