Jumping from version number 0.7.1, Mapnik 2.0 is a major release. While we mentioned Mapnik quite a few times, I don't hear that often about it. That said, many of us experience Mapnik frequently, since Mapnik is used for the rendering of OpenStreetMap's main map. Hey, Mapnik even participated to this year's WMS shootout.
Here's a reminder of what Mapnik is: "Mapnik is a Free Toolkit for developing mapping applications. It's written in C++ and there are Python bindings to facilitate fast-paced agile development. It can comfortably be used for both desktop and web development, which was something I wanted from the beginning.
Mapnik is about making beautiful maps. It uses the AGG library and offers world class anti-aliasing rendering with subpixel accuracy for geographic data. It is written from scratch in modern C++ and doesn't suffer from design decisions made a decade ago. When it comes to handling common software tasks such as memory management, filesystem access, regular expressions, parsing and so on, Mapnik doesn't re-invent the wheel, but utilizes best of breed industry standard libraries from boost.org."
Here's the list of major new features for Mapnik 2.0.