Sony is only keeping it free because they know it would piss people off if they start charging for it. But they know that they could use the money. PSN is probably the biggest loss for them on the whole PS3 thing. They started charging developers/publishers for putting content on PSN a few years back to keep the losses under control.. In case you missed that:
http://dlb-network.com/2009/03/sonys-publisher-fees-are-hurting-online-content/
Whether PSN is up there with XBL or not is debatable, and since I haven't touched PSN in a long while, I can't comment on that, but there are still some XBL features I bet players prefer that apparently PSN still doesn't have, like the party system and chat in every game and cross game, but that's not a lot to go on. Maybe PSN will implement those soon, but I doubt it would be possible to support it in every game without increasing load during gaming. Sony is obviously a hardware company, and on the software (OS) side they have always been playing catchup (or ketchup,, I'm hungry..) with the X360.
But you gotta love PR talk.. They can always turn something they actually dislike into something positive..
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