Well, if it adds anything to the discussion, my RPG group had given up entirely on 3rd edition about 4 to 5 months before we heard that there was even going to be a 4th edition. The combination of its "everything's generic," "everything involves 20000000 ongoing modifiers to track, some of which stack and some of which don't," and the fact that you had to use information scattered between half a dozen books or more to make any class except wizard, cleric, or druid interesting to play at higher levels, which became a bookkeeping nightmare ('we're using pages X to Y of Bo9S, but not pages Z to C, or was it Z to B?'), made us abandon it in pure frustration.
Really, it was the fact that you had to use material (some of it dubiously balanced) from up to a dozen splatbooks to make any classes except wizard, cleric, and druid versatile and interesting at the higher levels, that finally drove us wild enough to toss the whole thing over as a bad business.
I tried creating a "Book of 9 Swords" list of powers/maneuvers for the other "dull as dishwater" classes (fighter, barbarian, rogue, ranger, and yes, even paladin, although at least the last two have a few spells to spice them up -- although I wanted a wilderness archer rather than a nature priest with a bow), but the volume of work involved was inconsistent with the demands of running my own small business, and I reluctantly abandoned the project.
I'd given up on role-playing as a hobby until someone I know told me that 4th edition was in the works tempted me back to the boards. And lo and behold, I saw that 4th edition was at least promising to give all the classes maneuvers/powers so that, maybe, they'd actually have something to do other than hit or miss or try to trip someone (God, I came to hate Trip with a passion). So, in three words, I was sold.
So it seems to me that a sequel that fixes a problem in something you badly want to like, but that doesn't work the way you want it without tinkering beyond your power to perform -- and which removes the said problem as one of its main features -- can have the opposite effect, by re-engaging people who had regretfully shrugged and moved on.
I think these D&D iterations are a bit more like car models than movie sequels, myself. One presumes that it isn't a marketing mistake to put out a 2009 Ford, as a random example, simply because 2002 Fords already exist. The old ones are showing their age and starting to run not quite as well as once they did. Some people will keep restoring them, sure, and they'll work fine for many more years. But the average consumer is going to want to ditch the headaches of the aging system -- even if the headaches are minor, they're still there -- and try a new one. They know headaches will occur with that in time, too, but there's a period when everything is smooth sailing.
That is the appeal of the new model of D&D. Not that it's perfect, or that it'll last forever, but that it sweeps out the clutter and promises several years of renewed gaming pleasure. Without tanglefoot bags, I hope.
