XBox Live is doing pretty well.

[A Black Falcon]

Yeah, the Dreamcast. Note that that console died rather quickly. Also, it and PS2 mostly use monthly per-game charges... X-Box Live has a one-time charge for the first year. That is a different system which is much better... it still does have some extra charges, but its optional... closer to, but not as good as, PC games which, except for MMORPGs, are almost always free to play online.
Free online gaming will, I bet, always be more popular than pay online gaming. Sure, lots of people play MMORPG's online (or PS2 games), but nowhere NEAR as many as would play if they were free... and it goes the other way (most free games would get a fraction of the number of players if they required charges...)
I know that I've never paid to play an online game and, for the time being at least, I won't start to do that anytime soon. I'd FAR rather spend my money on a new game instead of on monthly charges that could total $120/year for ONE game (since most seem to be about $10/month... thats enough to get 3 or 4 games, minimum! No way would it be worth spending on the multiplayer for one game...