Sony has announced that, from February 7th, PlayStation Network accounts will be re-branded as "Sony Entertainment Network" accounts.
The name change has caused speculation to run rampant on internet forums. In the past hour I have read everything from, "Sony wants to change the name after last year's infamous network outage" to, "Sony is moving away from the PlayStation name altogether."
Ultimately, to this writer, it seems like "Sony Entertainment Network" is an easy umbrella term to use for Sony's increasing variety of online services. As it is, the Sony Entertainment Network also includes video and music on demand services. If they branch away from the middling Google TV for integrated television apps, I imagine those will be part of the "Sony Entertainment Network" as well.
Current Sony customers don't have to do anything for the name change tomorrow, though there will be a new Terms of Service Agreement that you'll have to sign.