Apple if it can be counted because they are taking away the gaming market and major publishers are cashing in on the success of Apple by releasing mostly shovelware rubbish for an inflated price
If not I'd have to say Microsoft due to overpriced peripharals, dodgy HW at the beginning of the generatuon, and a lack of variety in the game line-up exclusive-wise. If it's not a shooter it's not exclusive to the 360.