@libellule,
You have another but to think about and that is cost of entry. If people are waiting to purchase a this gen system for GTA series as the driving piece of software then the console cost enters the equation.
MS is certainly in the better position to drop the cost of entry to sub $200. No matter how you slice it the 360 has dropped at most $50 on the main SKU and $20 and $30 on the other SKU's. In 2.5 years this is incredible. They can drop the cost of entry easily to the following if they want to.
Arcade $199
Premium $279
Elite $349
Libraries sell systems not individual games







