Sony Playstation 3 has a major advantage in the form of the free PSN service.
Sony Playstation Network is a single stop destination for PS3 gamers to connect with each other, share and buy stuff and so on.
The company however is rumored to be working on a paid subscription based service on the PSN that would bundle something extra.
Sony is unlikely to change any of the existing free features that are accessible to PSN gamers. That is going to be a PR nightmare for them.
The company is already facing a lawsuit for removing Linux support on Playstation 3 through a recent firmware update.
Sony would have to deliver something really worth it to charge for this new service if they want gamers to pay for it!