There's an interview with Mike Mearls here and some additional discussion on EN World here that spurred this post. The short version is that it looks like WOTC is adopting Paizo's core approach:
- Paizo puts out two Adventure Paths per year, with separate supporting books for players and DM's
- WOTC will put out two "stories" per year, with at least a supporting source book aimed mainly at players
Now Paizo also puts out additional material like poster maps, flip-mats, cards, and sometimes miniatures for each of their AP's but they have been doing this for a while. WOTC will likely be doing a little more than this too, from miniatures sets to a special DM screen (they did one for Tyranny of Dragons) to tie-ins with the Neverwinter MMO.
They also note that they have plans through 2018. I think that's interesting because I don't think Paizo plans out their AP's that far in advance other than having a pool of ideas suggested previously. I suspect part of that may be that WOTC is deliberately drawing on D&D history and has a list of the first ten or so things they want to tackle while Paizo has less "legacy" to deal with given their separate campaign world.
It is interesting too in that up until very recently all we heard was that "adventures don't sell" - yet Paizo found a way to make that work. In fact, it's to the point that now WOTC seems to be basing their whole approach around a similar adventure-centered concept. What changed? Did gamers suddenly decide to spend more money than they did in the 90's? I'm going to say no. I think building a fair amount of setting material into the adventures probably helps, as does tying a source book for players to a set of adventures.
I also think it's interesting that WOTC's D&D team is smaller than Paizo's Pathfinder team. Both of them use a lot of outsiders/freelancers. Maybe it's just setting more reasonable expectations for tabletop D&D at WOTC - if so that seems like a good thing to me. It will also be interesting to see if it stays that way.