I think they just set a flat rate of $3500 and they discount it to zero for the 1st year to get as many weeks enrolled as possible.
Then, over time, they can give bigger discounts to platinum owners who are the key to the whole internal system success.
I tend to agree with some of the principle points you've outlined. To get the product off to a good start and to entice owners, I'd also venture to guess there will be an initial free enrollment period, or a very minimal fee. I think what happens here MAY end up being a reflection of what happens with the Asia Pacific points program. I'm guessing the buy ins there are not necessarily a precursor, but a testing grounds of sort for here. If owners there balk at the $5000 price, then it is more likely we will see significant grand-opening specials.
As for current resale owners, my guess is that at the end of the day there will be a grandfathering, and they will make the same initial offer to all owners, but I think that window overall will be shorter than the year you suggest (perhaps 6 months). I think they want to start off with a bang, and it is human nature to push the papers aside. A 6 month initial offering would get the ball rolling and, if met with success, will force others to join so the program will become self-sustaining.
And I think that at the end of the initial enrollment- which might entail more of a small sign-up fee to cover costs-the discount will slowly decrease (possibly 50% after 6 months, 40% after 7 or 8 months, etc.) so that a year after inception there is a fixed price- a MSRP, as you suggest. This sign-on fee will likely be waived as special offers to entice buyers to buy direct, with different promotional offerings much akin to different up front point incentives.
Perry, of course, you may end up being right, but I like to think of Marriott as a company more positively, and I think they are concerned with their customers. I may be naive, but at the end of the day I think that, at least initially, resale owners will receive the same offering. They don't want to create bad will towards a program at its inception, and if they alienated current resale owners there would likely be a lot of negative publicity from a significant group (and, since many resale owners are also direct purchasers of one or more properties, it would likely be a significant group), and I believe there would be credibility to complaints that a system that they bought into was being changed so that they would no longer enjoy the same benefits relative to other owners. While Marriott reserves the right to change the program in the future, there was no language indicating that they reserved the right to subjugate a certain subset of owners. I do agree that it is likely the distinction will be made for future resale buyers, even though I prefer it wasn't.
Of course, that's just my musings based on your speculation, nothing more.
I think an important consideration that there hasn't been much conversation about is the very real probability of point devaluation over time IF Marriott decides on a variable point system (wherein different properties of like season/view are awarded different point values at the onset). Just as many developer purchasers never thought about the future of Marriott Rewards devaluation and there was a huge outcry when that happened, I think that is a very real probability if the system is designed in that fashion. Even owners of the category 7 properties, who will be the winners in such a system, may find themselves losers 5 years down the road even when booking what Marriott consider equivalent properties. I'd hate for my 7 days to be suddenly worth 5 days when exchanging (of course assuming they'd be fixed when booking my home resort, which may or may not be an assumption that can be made). The precedent has been set by devaluation of the perk of trading for reward points, an explanation for why that is necessary over time has been validly offered; there is every reason to expect that IF Marriott adopts a variable point system where different Platinum weeks, for example, at different resorts are awarded different point values based on 2010 parameters, that down the road a new resort will likely be more expensive and will likely be awarded more points.
And, just like the decrease in resale value, this also affects EVERY owner.