I think either xbox or nintendo is going to make the next system. Not for a couple of years though, at least like 5 or something. definetly not playstation though.
nintedos old but they seem to keep up with tech but around 2019 they wont be up to tech and micro soft they have bill gates so they are standing strong untill 2021 then the stock market crashs and boom chaos sony umm I really dont know
I'd guess Microsoft. They got the 360 out a year before the other, and the previous XBox lasted 4 years. I'd expect the Xbox 720 a bit before Holiday Season '09.