I opted to go with the Strogg who had to buckle down and defend against the GDF. The demo region is a water valley that has been taken over by the alien Strogg and been contaminated. The GDF go in and complete a series of objectives that eventually lead them to infiltrating the Strogg stronghold and blowing up the Contaminator Device.
We aim to hold them back.
For the record, we kicked some ass and won the 20 minute LAN session. Overall the experience was enjoyable and got more fast paced as the GDF closed in. We had about 24 players in the game, so it got pretty involved as the objectives were completed.
Despite the quickening speed, it really counts on the GDF squad to perform the objectives, otherwise the Strogg have nothing to defend against. Given a competent enemy though, everything naturally falls into place. Each of the teams have their own vehicles too. From mechs to airborne ships, it really makes the surface-to-air combat more in-depth.
There weren't any glaring faults in Enemy Territory, and the multiplayer action was very fun, but PC gamers won't find it completely new ground.