PX/Xbox fans are so desperate
Should have stopped at this point
Power package and the fact that laptops sold for profit makes it impossible. Same for mobiles.
Consoles as they are now always will be a better value for same price
And the fact that it's a specialized device will always mean that it performs better than general-purpose solution of the same level. And I seriously doubt market for specialized devices will disappear.
General purpose OS like Windows will always have parts that are not needed for gaming (and general purpose hardware too, for a lesser extent), increasing the cost to run these OS.
And specialized gaming OS like SteamOS just turn PC into overpriced console, loosing ability to do general purpose tasks - no value for mass market