Explosive, in all cases.
My main gripe with this game is the campaign, the story in particular. The story just doesn't make sense, and the character I play always gets shot in the face at some point. The events seem thrown together, and basically jump from one cool moment to the next. That would be fine, but it all kind of blends together which dilutes the experience. Overall it is a lot of fun, with great visuals. The sound is good, but could be better.
Special ops is a great compliment to the short singleplayer. Teaming up with a buddy online, or split-screen is a lot of fun, and the missions seem varied enough, and offer a lot of challenge for expert Call of Duty players. I would also expect some spec ops DLC to come this spring.
Multiplayer is super faced pace and explosive. It allows for a lot of customization of your weapons and "perks". If you want to play as a run and gun guy you can, but you can also play as a stealthy class if you like. This is great, but I feel like MW2 rewards the "run and gun" type players more than they do others. Kill streaks are a lot of fun, but it is very hard to get them, so the better "run and gun" players are getting kill streaks, which makes them even better.
The multiplayer doesn't feel very team focused, and is more about the "lone wolf" style of playing.
Overall a great purchase if you plan on doing multiplayer and/or spec-ops, but if you are just buying this game for a single-player experience, you might be better off spending your money elsewhere.