I spoke to NASA space operations chief Bill Gerstenmaier at Kennedy Space Center last week, immediately after the post-launch press briefing, and I asked him about the timing of the decision and announcement for Atlantis retirement, whether retirement is this September, after the Hubble Space Telescope STS-125 mission, or if it is after two more missions
After pausing he said that a decision would be made after STS-122. I was surprised by this as I had been told "in the spring" before
Later on I was told by a western European space agency official that NASA had already essentially decided to continue with Atlantis because of the flexiblity in missions that it gives them.
I had already written about NASA's ordering of long lead items for the Shuttle to Station Power Transfer System and its application to Atlantis would mean a five extra-vehicular activity per mission capability for all three of the remainng orbiters, giving the agency maximum flexiblity for the remaining nine missions (after STS-125 and including those so-called "contingency" missions)
It also makes public relations sense to announce the stay of execution immediately after a successful mission. So expect to see more of this!