So people are starting to port their apps to introspection from the about-to-be-obsolete PyGtk+ bindings and I'm getting questions in #python @ GIMPNet about how to get the latest and greatest version without having to build stuff.
For those in Fedora: you can get it already from F15, will be backported to F14 after it's out.
For those in Debian: watch experimental for updated packages soon.
For those in Ubuntu: update to Maverick and watch the telepathy PPA for updated packages soon.
Update from comments:
For those in openSUSE: you can get it already from openSUSE Factory, and will be backported to 11.3 as part of the GNOME 2.32 backport.
For those in Microsoft Windows: no binary packages have been built at this moment and nobody is currently known to be working on it.
If anybody has corrections or additions, please comment and I will update the main post.