Beyond Unreal is reporting some new Unreal Tournament 3 demo details on their site. Though they don't list a source, those guys seem pretty plugged in, so I trust them.
The demo will likely feature three maps, none of which will be a Warfare map:
DM-HeatRay is planned to be in the demo. It is the destroyed urban environment that features a lone DarkWalker which is dropped in at specified times during the match. The level strongly conveys a UT-like city setting (complete with the occasional train running on an overhead track) is pretty stunning.
VCTF-Suspense is the second demo map. Set on an immense suspension bridge, this level is set up with Axon vs Axon vehicles and the action takes place in three planes: on platforms high above the bridge, as well as on and under the bridge. It has a nice mix of open sniping areas and tight corridors. There's a little water there too if you care to take a dip.
The final demo map may be DM-ShangriLa. This one has been seen in some of the videos before. It features buildings with Asian-themed architecture and the action takes place around a courtyard.
Hit up the site to read why Warfare maps don't make sense for the demo... and what a Warfare map is.
More UT3 Details [Beyond Unreal]