I think it's hard to link this new value resort with the possibilities for other DVC resorts simply because the demand for values is so very high. While I'm sure they have an integrated lodging strategy that considers occupancy and revenue at a high level, I'm even more convinced they also have very specific strategies at each resort category/level. I think it could be more likely that other resort development WON'T happen right away specifically BECAUSE this value is being built, i.e., they've prioritized adding value rooms.
So yes, I think they are responding to that specific demand. Adding a value is a great thing financially - they have set expectations lower so the staff requirements are lower. Plus those guests are all going to the same parks and shopping and dining in the same places. Perhaps they're spending to a lesser degree, but still - if 1 value guest spends $25 a day in shops and 1 resort guest spends $50, there are still a LOT more value guests. Who knows how it averages out, but their spending power as a collective is mighty IMO - but they won't spend as much if Disney doesn't get them on property and keep them there. And they have much less chance of converting them to moderate, deluxe or DVC customers if they don't experience the "magic" of on-site first. And I'm VERY curious about the numbers - are value resort guests more likely to purchase a dining plan, even if it's just the QSDP? I'm convinced the DP in general is a big money maker for Disney, so increasing the number guests who are then able to purchase the dining is ideal. (And let's not forget it's yet another way to lock people into staying on property 24/7.)
Anyhow, the short answer is that I do think we're at a temporary saturation point for DVC, but that will change as the economy changes and as Disney expands its resort guest pool. Getting more guests on-site is their best strategy for getting new DVC buyers. And I'm sure when they feel the time is right to expand, be at the the moderate, deluxe or DVC level, they will have no shortage of plans already in the works from which they can choose.