I loved the ODST campaign. I think it was one of the best other than Halo CE. (I have to admit I pissed my pants while playing that for the first time...). But once more, Bungie expands their intriguing story-telling. It's a nice change from Master Chief, and it's nice to view things for a different perspective. I don't recommend buying it though, as it is a little short, around 4-6 hours.
Currently playing MGS2 (360) and Super Mario 3D Land (2DS)