MS will release there "Service" in 2013, but it will be in its infancy for a while because they will be most likely buying exclusives for development this year and next year for this service and considering it takes around 2-3 years to develop a "good" game for a next gen platform.
SONY will start there studios developing titles for there next system next year and many of them will make one more title for the PS3 before moving to develop for the PS4, example Uncharted 4 (or 3) could be the last uncharted Naughty Dog makes before moving on to create a new ip for the next system.
But we all know that SONY will not release a system with low support and would want its first year to have a array of big hitters from its first party studios and a few from 3rd party to go along with the array of ps3 ports of games that are released that year.
Of Course That's Just My Opinion, I Could Be Wrong
