As it turns out, making a 4th release in 2012 wasn't going to be easy! Thanks to the testing of David Reid, we found and fixed an issue with pip which was making installation difficult when zope.interface was missing. And we got another fix with the help of Eric Mangold, fixing the compilation on OpenBSD.
The tarballs of the second pre-release can be found here: http://twistedmatrix.com/~therve/12.3.0pre2/
Thank you for testing it again!