Taken from a forum thread on the officials for LoTRO.  My stuff, just copied and pasted here.

Some things. WoW's graphic style is specific to their previous games, and it is a bit cartoonish. The newest generation of fantasy based MMO's are going for the "Holy S*** Batman!" factor as far as I can tell. These new arrivals are looking better than WoW, and still able to keep the minimum system requirements close to that of Blizzard's cash cow. It may still be a year or two before Blizzard really feels the pressure to take it up a notch, but they will have to create something to keep all the WoW players from going to other better looking and/or less expensive game options, and I don't think another expansion and ten more levels of the same thing will be sufficient. The Guild Wars series helped get this exodus underway 1.5 years ago. It may not have been the final nail in the coffin for WoW, it was surely far from it, but it did rouse the undertaker for sure. Slowly players are being siphoned off by other games that offer different and in some/many cases better experiences than the aging MMO king.

When a ruler begins to age, the younger nobility gets antsy. Typically when a king gives up the ghost, his crown is passed to his designated heir. (Stay with me here.) What has the potential to happen in the case of the king of MMOdom, is that the kings heir (Blizzard's successor to WoW) will either be too young, or non-existent, creating a power vaccuum and leaving the throne of MMOdom prime for the taking by any able member of our young nobility. (Other good MMO's.) What I hope happens, is that Blizzard's heir is in fact too young, and that LoTRO will be able to come in and assume the throne, unsteadily at first, but gaining support as the content of it's character shines through. (I lol at myself... Really.)


*Don't hassle me about inheritance minutia. I know it's not perfect but it makes the point.*

That said, Blizzard is already working on something that will allow the throne of MMOdom to be retained by a member of it's cartoonish family. It's in the works, be it Diablo III or WoW II. I'd bet the Shire on it.