Update (2010-02-18): http://sgillies.net/blog/1001/shapely-1-2b1
Update (2010-02-09): 1.2a6 (12 cumulative bug fixes) is ready at http://gispython.org/dist/Shapely-1.2a6.tar.gz.
Shapely 1.2a1 has been tagged and uploaded to http://gispython.org/dist so that people don't get it by mistake from PyPI. To install and try it out (in a virtualenv):
You'll need a GEOS version >= 3.1.1 to try the new prepared geometry class:
Most of the work toward 1.2 has been done by Aron Bierbaum. Other features include geometry simplification, a switch to the new reentrant functions in libgeos_c, setup script consolidation, and more tests.