After about three weeks of testing, the whole xorg 1.15 update (including new mesa and packages new to the repositories) is ready to move to all users.

KDE 4.12.1 was build last week, brings more than 45 recorded bugfixes including improvements to the personal information management suite Kontact, the UML tool Umbrello, the document viewer Okular, the web browser Konqueror, the file manager Dolphin, and others. It is included in your next update too.

Besides the above, a few more base packages had major updates, requiring rebuilds of many, so this is a large update. Best practice for this update, first make sure your mirror is fully synced:
mirror-check
UppubDate:
sudo pacman -Syu
And answer "yes" to the replaces questions pacman asks.