Before I dive into this project (as I usually do), I decided that it would be reasonable to do some research into the development of virtual worlds.
Currently, I'm reading Designing Virtual Worlds by Richard A. Bartle. Bartle is usually known as the Father of MUDs, as he's often attributed with creating the first one (though he points out in his book that this isn't so).
I'm almost a third through the book, and it has been interesting reading so far. I kind of see Bartle as the Dr. Phil of virtual world design, in that everything he's saying seems like common sense, but it isn't until he actually spells it out that you know it.
I mean this as a compliment, because the "common sense" of virtual world design isn't anywhere near as obvious as real-world common sense is (thus the "common" part). But none of his discussion seems wild or out-there -- and you realize that it's good to have an old hand guiding you, so you don't make the mistakes of others. "History repeats itself" is very true in virtual world design, both good and bad.
I've also picked up Developing Online Games: An Insider's Guide by Jessica Mulligan and Bridgette Petrovsky, but haven't cracked that book yet. Also ordered and apparently on its way is Theory of Fun for Game Design by Raph Koster. I'm looking forward to this one because Koster was involved (Lead Designer? Producer?) in Ultima Online, which is my jeu du jour.
Additionally, I'm subscribe to the MUD-dev mailing list, but admittedly all the messages get stored in a folder right now for lack of time to read them. This, I expect, will be a great source of information, since it's more "live" than a published book -- though established knowledge is just as good as innovation!
I also frequent the occasional blog that talks about MMORPGs and virtual worlds, though not necessarily from a developmental point-of-view.
With all this reading, will I ever get to designing and writing this engine? Sure, but I want to know that the initial decisions I make are reasonable, and aren't going to make me start over again (and again).