Yeah, Ballistic Weapons has completely revived my desire for UT2004 too. It's just so awesome! It's customizable, very gory, has a lot of weapons and tactics, and can be played in any gametype!
Although some weapons are a bit too powerful, especially in Loadout, where you can select those weapons. Such as the pineapple. Charge up a throw/set it to long throw, pull the pin early, and throw when the grenade is going to hit your opponent. Guaranteed kill!
And the landmines are very cool in some maps, especially when you open them (the mines jump out from the floor/wall/ceiling), such as in DM-CBP2-Masurao.