You might have some others, but those above are the repos that are central to Tumbleweed.
To prepare for 12.1 (or to switch to 12.1) you simply change the first three in the above list from the “openSUSE” repos to the corresponding “current repos”, and achieve the list as follows:
openSUSE Current oss http://download.opensuse.org/distribution/openSUSE-current/repo/oss/
openSUSE Current non_oss http://download.opensuse.org/distribution/openSUSE-current/repo/non-oss/
openSUSE Current Updates http://download.opensuse.org/update/openSUSE-current/
You can do this now, before 12.1 is released, or later. Why? Because the three addresses at the top of the second list are actually links to the correct contemporary addresses and the developers will make sure they point to the correct repos before and after the transition from 11.4 to 12.1
Priorities: I recommend you leave them at the defaults (equal across all repos) for the transition (and afterwards).
Tumbleweed is designed and tested by the maintainer (Greg K-H) to have only equal priority across all repositories. You can have differing prioritoes if you know what you are doing, want to be more adventurous than the basic design criteria, but for average users like me, default priorities will (theoretically) cause least (dependency) problems. So, in a simple guide for average folk, to say anything about priorities would just cause confusion of the sort that you can see easily and often in the Forums.
WARNING: watch out for newer glibc. Despite the version number differs only by minor number, it is not fully backward compatible. So on one hand updating it does not trigger update of all affected software (see above – minor change), on the other hand it breaks some (not all) already installed software.
This issue is reported. I hope it will be fixed, but until then I switched back to 11.4 repos.
The openSUSE-current links appear to be useless…if you add them it looks for a dvd description file with 11.4 as the version in the oss dir when reviewing metadata. If you choose 12.1 it correctly pulls the 12.1 file that is actually IN the repo.
Sadly, the 11.4 based tumbleweed repo is gone, it should have been kept for those of us who wish Gnome 2.x in a transition period. I myself use it in dualboot with 12.1. Another expectation that was mentioned in another thread, is to lock down Gnome 2 packages with YaST before upgrading to openSUSE Current (12.1) tumbleweed. I wonder if this will work when the Gnome 2.x packages are not compiled for the 12.1 base?