Classic bait and switch.  One of the appeals of the PS3 over XBox360 is that the online portion has always been free, whereas XBox has always charged for their XBoxLive service.
Well, now that PS3 is doing well, they're considering charging for the PSN service.  http://games.slashdot.org/story/10/02/04/0727249/Sony-May-Charge-For-PlayStation-Network  There will likely still be a free component for basic online play, but if you want to download demos, or get onto Home, or access special downloadable content, you need to pay for a subscription.