For me, the key moment in xXx comes near the end of the film, when Vin Diesel pushes aside a police sniper, grabs a bazooka, and says, "It's time to stop thinking cop, and start thinking PlayStation!"
The whole movie is the ultimate computer game. Set in a lovingly recreated Prague, there's the motorbiking level, the skateboarding level, the undercover cop level, and - best of all - the snowboarding level. The good guys are indestructible, the baddies speak in bad Russian accents, and everybody has a huge torso, seemingly made up of a limited number of polygons. Why there isn't an X-Box version of Triple-X is beyond me.
In plot and style, the film is James-Bond-meets-Die-Hard. There's gadgets galore, jokey put-downs, spectacular explosions and awesome action sequences. The mountain section, where Vin Diesel outruns an avalanche by snowboarding down vertical drops, got a spontaneous round of applause from last night's screening audience.
It's fun, it's dumb, it's exciting, it'll do wonders for Prague's tourism coffers, and turns Vin Diesel into a proper movie star, despite looking like Deputy Dawg on steroids. Go see.