Madden 08, from all initial reports, sold out on Xbox and has done tremendously well. It could wind up selling ~100,000 copies.
Not only this, according to a recent statement from Neilsen ratings, Xbox is still played about twice or more often in the US vs. the Xbox 360.
Hardware wise, the Xbox is pretty much beyond DOA. MS stopped the factories in August 2005 and never made another unit - despite the fact that the Xbox was still selling really well (if your wondering, had MS of kept Gamecube-like shipments up, the Xbox probably would of sold another 1-3m units if not more).
The GC is almost dead - it's still selling hardware in various regions in the thousands per week. Software wise, I haven't seen much available. Nevertheless, I assume that there are still going to be a few titles made in the future.
The Dreamcast - there are still a few hombrew and other games being released. A Dreamcast game released earlier this year in Japan to 10k+ first week sales. Not only this, Sega announced last year, that due to high demand, they would be re-releasing the Dreamcast and selling the refurbished Dreamcasts because there was still a good bit of demand. Of course, these units are not counted.
Back from the dead, I'm afraid.
