Sony Charging for PSN Services?

One of the many differences behind the Playstation Network is that unlike its competitor (Microsoft's Xbox), Sony does not charge for it's online service. PSN users might be in for a change though as supposedly, charging for PSN service is something Sony is looking into doing. Back in November of 2009, Sony had a paid subscription plan in the works for PSN. Peter Dille (head of PSN) mentioned the following in an interview with IGN:

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.

The question that remains is what exactly the charges will be. Will online multiplayer be charged for (much like Xbox Live) or will Sony offer premium services and other goodies to encourage people to pay while leaving the current offerings for free? The gap between the console wars might not be as far apart as there currently is. Sony fans will still have Blu-Ray to look forward to at least. What are your opinions?