The Death of Online Gaming's Monthly Subscription Model

Star Wars: The Old Republic has been the inspiration behind many editorials over the last few months, and Ars Technica's Kyle Orland has contributed his own to the pile. While he uses The Old Republic's switch to free-to-play as a springboard, his editorial actually focuses more on the wider MMO market.
The death of the online game subscription is surely unwelcome news to some gamers, who still associate free-to-play games with vapid, social gaming clickfests or pay-to-win schemes that kill the spirit of fair competition. But those stereotypes are getting less salient as a wider variety of games make the model work without compromising their traditional gameplay.

And while some gamers may grumble, in aggregate players are overwhelmingly voting for free-to-play with their wallets. Lord of the Rings Online saw its monthly revenue double after it stopped requiring subscriptions in 2010. DC Universe Online saw a seven-fold revenue increase when it did the same late last year. Even the venerable Team Fortress 2 started bringing in 12 times as much money when it switched to a primarily hat-based business model. I could continue, but you get the idea.
It's certainly not a surprise to see more and more games going free to play in the wake of financial difficulties, though I think most interesting is that the article suggests World of Warcraft may eventually have to move on to a free-to-play model in the future as well, as its stalwarts begin to move on to other titles. Are MMOs with subscriptions a dying breed, or was World of Warcraft ever only an exception to begin with?