I think it's about time the gaming industry realizes The One Truth:
- MMO gamers usually play a single MMO at any given time.
There's no point in releasing one MMO after the other, since the market is smaller than it seems, especially considering the development costs. Investors look at WoW and go "oooo, potential to become BILLIONAIRS!". They should be looking at WoW and go "odd one out".
I'm not saying you can't have more than one successful MMO at any given time. I'm just saying you can't have dozens. The market's just not big enough. It's nothing like the single player market where you could, potentially, buy several games per month (if enough good games got released).
Age of Conan is currently estimated to have around 100.000 subscribers. WAR has somewhere along the lines of 300.000. World of Warcraft, on the other hand, is still growing, and has passed 11.500.000 paying accounts (quite a few players own several accounts though).
Both Funcom and Mythic has made a good effort to steal some of WoWs playerbase, but as the numbers indicate, they've failed completely. I think SW: Tor will probably be a success, but it's not going to be a new WoW. Not even close. WoW is, as I've mentioned already, the odd one, and only achieved such status due to a set of circumstances that is unlikely to repeat itself (the discovery of the casual MMO market among other things- MMOs prior to WoW usually required exceptional dedication to get anywhere).