Even when the site was up the beta servers couldn't cope with traffic the beta released created. Let's hope that DICE can deal with the problems and get them fixed (is that not what a beta test is for).
The same map 'Port Valdez' is available in both the Xbox and PC beta tests. With up to 24 players on Xbox and 32 on PC featuring the Rush multi-player mode. Vehicles include Quad bikes, Battle Tanks and Mobile Armour.
You'll have to wait until February 4th (Europe) and February 11th (US) for the PlayStation 3 beta test release.
The full game is due to be released on March 5th (Europe) and March 2nd (US).