while inside the game playing. the online experience is identical. virtually no difference. they play exactly the same.

outside the actual game playing xbox is "smoother". its a little easier to connect and communicate with friends, thats why.

This site is dominated by PS3 fans. Yeah i'm new and figuring it out now.

Where did you draw that conclusion from? Why is it even relevant?

Probably the number of posts in this thread saying how good PSN is, in fairness he's right that there's a lot.

I never notice much difference in lag except in some third party games such as Assassins Creed Brotherhood and GTA IV (a while ago) used to have speed issues matchmaking and stability problems on occasions on PSN.  I haven't done comparisons on COD or anything recently to really comment further though.  I have seems weird firewall issues cause the odd problem with parties on XBL which required friends to reboot their routers to stop disconnections.  

I think they're very similar but I believe the extra control Microsoft has over matchmaking servers can produce better results particularly at peak times.  This is my opinion and in no way fact as I don't have the time and energy to start testing the theory scientifically.

I have quite a few issues playing Halo 4 online but after doing some research I found out that its a problem from 343.

Only got Ps3 but never had an issue with PSN, and played Live on mates consoles in the past. Could never
tell the difference on games of FIFA or Battlefield. End of the day servers arn't gonna influence if someones connection itself isn't up to speed.

Although I do have to do a lot of port forwarding to get Fifa / Demon Souls / Battlefield to work online properly on Ps3, which might not be a problem on 360? Something I'm used to doing and dont even think twice about but could cause problems to some who are less knowledgable about such things.

Yes it does, the way matchmaking works on each service would mean deciding if you get to play with mainly those closest to you or crap games with someone halfway across the globe.  Then there is a element of whether there is efforts by the console manufacturer to limit match making within regions or not.  Just because you haven't noticed a difference doesn't mean there isn't or cannot be.  Items such as more ports being required by the different services could also have a bearing on user experience.  I think your main point is probably that the host connection matters most ultimately which is of course accurate.

Maybe there are more PS3 fans here because PSN is smoother.  Very logical.  Or maybe they are just gamers who just prefer the PS3 one reason being that PSN is better.  More logic for you.  Does everyone who prefers a PS3 and/or PSN has to be a PS3 fan?  Nope.  Maybe you prefer Live because you are an Xbox 360 fan, no?

I have started online gaming at PSN. Never had a problem with it. Then I signed up for Xbox Live Gold for a short period, had a good experience as well. Now I have been a PS Plus subscriber for about 2 years and the online is the same quality as the free members get and just as good as Xbox Live Gold.

All in all, both PSN and XBL are very smooth (considering my internet connection and games I tried). I like PSN+ better obviously because of all 'free' games, discounts and other benefits, but XBL has cross game chat that some people really like. PSN has cross game chat only on the PSVita.