What is the potential lifespan of an MMO?

No people will not be playing the exact same games as us in 10 or 15 years, for one simple reason:

MMOs evolve. The people playing Ultima Online now are playing a different game from those who played UO when it started. I am still playing EVE (albeit intermittently) after 4.5 years and it is a completely different game from when I started to play it. Expansions, patches, addons, and the way a community grows and evolves all contribute to the fact that MMOs change over time. So we may well be playing games with the same name a decade down the line but the game itself will be different.

That being said I do think that WoW is on its last legs and WotLK is nowt but a last gasp as it slowly slides into oblivion.

/me waits for the flaming to begin.

Technology will improve, and when it's possible for our kids, then bingo... Disneyland will be already there fully realized for them to come and play. I speak, of course, of World of Warcraft.

The game analogy isn't as real as the theme park analogy.

World of Warcraft, as virtual real estate, will never go away. People a hundred years from now will meet online using it... but while wearing goggles and full-body sensory devices.