I'm guessing this was part of yesterday's PS3 firmware upgrade:
The Facebook PSN updates used to say something like "Joe Fourhman has purchased The Simpsons Arcade Game on the PlayStation Network." Now it seems your PS3 is going to offer up a little bit more detail, specifically promoting the PlayStation Plus service. While I like the new language, that yellow Plus icon is going to get pretty boring.
I'm sure most of my non-gaming friends have turned off the Facebook PSN notifications anyway.