The long awaited python 3.3 version is finally here! There are quite lot improvements and additions:

• explicit unicode literals - revived from the python2 series, the intent here is supposed to be easier porting from pythom2 to python3. [PEP 414]
• yield from expression - something that will ease writing of coroutines [PEP 380]
• ChainMap collection - in collections module of course, see docs
• ipaddress module - a wonderful addition for working with IP addresses and networks, with support for IPv6 as well, see docs

... and many more, see the release report. Also, a healthy discussion on hacker news