The huge success of D&D Online pretty much paved the way for any other MMO that needs a sudden boost in popularity to do this... and with a few notable gorillas/exceptions, that's pretty much every MMO. As more professional MMOs do this (which should have a very deleterious impact on the older crop of grindathon free MMOs), it will become harder and harder for others that don't have a sustainable momentum of huge subscription numbers or who offer something uniquely attractive to avoid doing so to prevent their subscribers from moving to another MMO which has a comparable play experience and is "free".
So WoW is fine for awhile though they'll feel the hit (especially as the game is quite old, expansion packs nonwithstanding), and something with the appeal of the Old Republic game can pursuade people to shell out money each month for at least a while, but something like, say, Vanguard: Saga of Heroes? If it still exists in two years, I'll be very surprised if it hasn't gone free-to-play. The more professional free MMOs there are, the harder it will be to get people to keep paying subscriptions. Some will survive if they can offer a unique experience and/or are unsuited to microtransaction economies (Eve Online may hold out a lot longer than most, for instance), but I very strongly suspect that very soon free MMOs will be the norm and subscription-based ones the exception.
Oh, and to illustrate my point, having cancelled my COX subscrip a few months ago (mostly due to not having any time to play MMOs on a regular basis anymore, although my unenthusiasm for Going Rogue was a contributing factor), once Champions goes free I'll install it again (having tried it out on one of the free weekends; I didn't prefer it to CoX by a longshot but it was an amusing change of pace). And if COX went free (which it most certainly will) I'd go back to it, most likely at the same once a week or so I was playing it before I cancelled.
So WoW is fine for awhile though they'll feel the hit (especially as the game is quite old, expansion packs nonwithstanding), and something with the appeal of the Old Republic game can pursuade people to shell out money each month for at least a while, but something like, say, Vanguard: Saga of Heroes? If it still exists in two years, I'll be very surprised if it hasn't gone free-to-play. The more professional free MMOs there are, the harder it will be to get people to keep paying subscriptions. Some will survive if they can offer a unique experience and/or are unsuited to microtransaction economies (Eve Online may hold out a lot longer than most, for instance), but I very strongly suspect that very soon free MMOs will be the norm and subscription-based ones the exception.
Oh, and to illustrate my point, having cancelled my COX subscrip a few months ago (mostly due to not having any time to play MMOs on a regular basis anymore, although my unenthusiasm for Going Rogue was a contributing factor), once Champions goes free I'll install it again (having tried it out on one of the free weekends; I didn't prefer it to CoX by a longshot but it was an amusing change of pace). And if COX went free (which it most certainly will) I'd go back to it, most likely at the same once a week or so I was playing it before I cancelled.