X360 - at the time it released, technically it was the best you could get (counting PCs as well), due to ATI creating for them powerful GPU with unified shaders (it took full year for that to appear on PCs, with nVidia 8800 series), very capable PowerPC CPU, eDRAM to help with AA tasks, and shared memory pool between CPU and GPU. Yeah, there was that "slight" RRoD issue, due to being pushed out of the gates too soon, but when it worked, it worked like a charm.
Library was really good, most multiplatform games ran better on it than on PS3, and if you were interested in such things, Kinect was quite a peripheral as well.