Sony may start charging for PSN?

Well, we can all blame Hulu for starting the no-more-free content movement, now since Sony may also start charging users for access to the PSN service.  This doesn't exactly encourage me to get the new PS3 I was considering, Sony.

The head of PSN revealed in an interview with IGN today:  "Maybe a longer answer to a shorter question, but I think there is just tremendous improvements to the PlayStation Network, which leads me to your last question: will we charge for it or why don't we charge for it? It's been our philosophy not to charge for it from launch up until now, but Kaz recently went on the record as saying that's something we're looking at. I can confirm that as well. That's something that we're actively thinking about. What's the best way to approach that if we were to do that? You know, no announcements at this point in time, but it's something we're thinking about. "

So what exactly will Sony charge me for?  The ability for multiplayer in online gaming, like how Xbox Live currently works?  Or perhaps for some premium content that they may push out?  Feel free to chime in, PS3, or would-be PS3 owners.