Ive been a player and DM for D&D since the days of AD&D 2nd edition. Once you get into it, its with you for the rest of your life, wether in the form of good memories, or an ongoing gaming group.
For me its been ongoing, although Ive changed groups a few times. Ive loved all the editions for different reasons (I even really like Pathfinder as it can be considered a spiritual successor to D&D, almost like an alternate 4e).
I have found that 4e is probobly the best ruleset the game has ever seen, and Im really excited about the upcoming Essentials line despite the controvery that seems to be going around about it. Personally, I think it will just make it easier for those unfamilialr with RPG's to get into it if they are curious.
In my time playing, I dont think D&D has been as widespread or as socially accepted as it has been with 4e. 4e's look and accesability, combined with the depth of previous editions has aquired a much broader audence than before. 3.X was too dense for most to penetrate if they didnt already have experience, but 4e eases you in nicely. The complaints for 4e really just boil down to a preferance - the MMO argument is silly as 3e was considered "video gamey" in its day - I recall alot of comparisons to Diablo 2. The only reason MMOs are being mentioned is because thats what is big today. If you really looked at the concepts of an MMO and at D&D, there is a wide margin. All editions of D&D have had "roles " for the classes - 4e simply named them (and even then it is possible to make a fighter that is a striker, for example) but never forces you into anyhing. Powers seems to be another hot button topic, but that has existed in different forms in the older editions as well.
MMO's have worlds that for the most part, the PC cannot affect - the same NPCs run the same quests all day every day (again, for the most part). MMO's supply you with your abilities as you level up and you are hard coded into a role (actually somewhat similar to older D&D editions, whereas 4th has a constant barrage of options) I know not ALL MMO's do that, but it is a pretty general trait. Basically, with any edition of D&D, you can do whatever you want, whereas in any MMO, or any video game for that matter, you are restricted to what is coded in. Not a knock against MMO's at all, its just that they are a different beast altogether.
The only thing I will admit to, and not in a bad way, is that since 3e, and continuing into 4e, the need for a battle mat has been pretty mandatory. Sure it can be done without, but many sacrafices must be made. 3e and 4e have been called "boardgames" because of it. Clearly that is not the case, but i can understand the sentiment.
In the end everyone prefers their own edition, be it OD&D, 1e, 2e, 3.X, Pathfinder or 4e. Any group can make it work, as that is the core of D&D: playing and having fun with friends. It all comes back to a game of imagination, regardless of edition.
