I dont think we will see a 720 till at least 2013 maybe.....as for it not breaking down as fast, all hardware can have faults at any time for any reason.....we can hope they have learned from the RROD fiasco but its all down to the components used and quality
of those components
hopefully you can do backwards compatibility on the 720 and be able to play with people who still have the 360. Also you should be able to play games like MW2 on your 720 online. so basically you can still play the old games but a altogether new console.
well 720 is as good a name as any currently till they officially announce and name , but a simply 3 digit number would keep with the branding they have used....worse case scenario...they name it Kinect...oh wait, they already failed with that!