As much as I hate the topic here, it should happen. World of Warcraft has been going on for more than 5 years, has the graphics and engine of the previous generation's systems, and other than fueling Blizzard with embarrassing amounts of cocaine money, has no real purpose in gaming anymore.
It was a fun romp through the beautiful forests, and interesting terrain when I played, but was considerably better when 60 was the cap, still fun, but slightly tedious when 70 was the cap, and now feels like it's moving into Sonic and Mario land with WOTLK and Cata. Wow really needs to die.
Not that we should remove blizzard's massive money erection, but maybe they should make a sequel, with a better engine, or maybe they should take starcraft into MMO land, or maybe they should do something else other than spend 90% of their funds on making this game shine. Warcraft 3 and WOW are all they've done over the past decade and it wasn't until a year or two ago that they said "Oh by the way! We're also probably maybe working on trying to begin to start a possible sequel to Diablo2 and Starcraft possibly maybe..."
So, when do you think will Blizzard sever the line between themselves and WOW? Will it still be going in a decade, or do you (like me) feel that the new expansions and patches are needless polishes on a game that's worn down and old?