It very much looks as if a successor to the Xbox 360 will now not be launched in 2012.
Why? Because we now know that Halo will definitely be an Xbox 360 title and not, as some had speculated, a launch title for the next machine.
Confirmation came from Frank O'Connor, the boss of boss of 343 Industries, who said on NeoGaf that Halo 4 will be on Xbox 360 and use a modified core of the Halo engine(s)”.
The obvious conclusion to draw is that, as has also been rumoured, a 2013 launch is now on the cards, with a likely reveal at E3 2013.