I play online on both consoles. I only play with real life friends when i play online. Always with headsets and in private chats.
Xbox live is almost always without any flaws or problems. The system they have for private chats and game invitations is genius and as easy as it could be, and most of all, it works. Most games work more or less lag free and without major connection issues, meaning they are playable and therefor result in fun times.
The PS3 offers no real private chat that will stay on, regardless if you start a game or a movie, whatever. This is a major flaw compared to the Xbox, especially if you want to use the private chat function because you always play with friends, and don't want to hear all the little kids screaming in your ears (and don't feel like talking to them either).
Regarding connection quality, lag, etc. I remember some fun time, and some equal ammount of frustration and waiting time with the PS3. I spent more than one evening waiting to connect to servers, dealing with router/hardware issues, loosing connection, etc. This never happend to me on the xbox to such an extent.
Game updates / Update downloads / Update installations seem to take longer on the PS3 aswell... more waiting time again.
I like both consoles, but i know exactly why i'm paying for xbox live, and i don't feel ripped off. On the other hand, i don't feel ripped off regarding the PS3, it's a great console, and to say something useful for this thread... i would buy it again, yes. But to say the online system is better... it's free, yes, better, probably not...
And now i'll go jump out of a window for taking part in another one of these threads...