Practically all big distributions have already switched to TL2012 or their upcoming release includes 2012. Debian/wheezy (currently testing, will be released soon) ships 2012, and I have already more uptodate packages of current tlnet in Debian/experimental.
Ubuntu from 12.10 onward includes TL2012 by default (same packages as in Debian). For 12.04 you need to use the mentioned PPA.
For Fedora 16,17,18 there are TL2012 packages, in 18 it is included (unsure here!)
openSuSE 12.2 has TL2011 package and TL2012 from an additional repository, openSuSE dev contains TL2012 by default.
FreeBSD and OpenBSD has TL2012 in the ports
NetBSD is in progress
Mac has MacTeX which is a repackaged TL2012, so you always get the latest updates, plus a nice integration.
Hope that gives a small overview on what is available.