The problem I have with that artwork is it looks "low-budget game". You usually see painted covers on games that have poor in-game graphics. I've always been a fan of game boxes that set a mood, and that would look good and important if an entire wall was covered with them. The starcraft box comes to mind. People like to be drawn into the game....that's just my oppinion.
I do like the effect the artist was going for, though - to show that flying is a major part of the game and that the jetpacks aren't auxillary such at Duke 3D's jetpack, which is accomplished by the weapon killing the person mid-air. Still, the background looks sparse and boring, and the weapon effect looks downright wimpy. A flag on the back of the dead player, explosions in the background, a blur effect on something, and a punched out logo (bevelled on the box) would all help, I think. I really liked the design of the TV banner at Tribal Wars.
I guess we'll find out what people think after the first week of T:V's sales, though.