What I'd like to see happen, but no company does this, is truly active support. Not just errata or a very brief FAQ, but active support with "official" updates or recommendations to newer material. A case in point is Trollhaunt. I'd like to see WotC provide an update to suggest monsters from newer-than-MM books that might apply to existing encounters. The additional material they provided is great, but I that stuff wasn't supposed to replace the current material. For example, would different supporting cast from newer books be a cool suggestion for the BBEG?what might it have to include
Regarding the 4E uniqueness, I think I understand what you mean. As anyone who has done converting can tell you, it's not so simple as plugging in new monsters. Frequently you have to rework part, if not most or all, of an encounter. Simply going from 3 to 3.5 was difficult as the spacing of Large upright monsters changed drastically. Thus, any 4E unique module will necessarily take into account 4E rules. A single monster of equal CR in 4E is a solo, for example. You can actively plan for skill challenges.
So like the Open Design Project that Wulfgang does?What I'd like to see happen, but no company does this, is truly active support. Not just errata or a very brief FAQ, but active support with "official" updates or recommendations to newer material. A case in point is Trollhaunt. I'd like to see WotC provide an update to suggest monsters from newer-than-MM books that might apply to existing encounters. The additional material they provided is great, but I that stuff wasn't supposed to replace the current material. For example, would different supporting cast from newer books be a cool suggestion for the BBEG?
At least with RttToEE we had a dedicated forum and built a detailed errata thread, a FAQ, and best of all the Best of the Boards. I haven't seen that for other WotC modules as hosted on their site. There are several threads here and there, but it's really difficult to search. If there were a location, I'd be happy to start these threads (as I did for Banewarrens).
Regarding the 4E uniqueness, I think I understand what you mean. As anyone who has done converting can tell you, it's not so simple as plugging in new monsters. Frequently you have to rework part, if not most or all, of an encounter. Simply going from 3 to 3.5 was difficult as the spacing of Large upright monsters changed drastically. Thus, any 4E unique module will necessarily take into account 4E rules. A single monster of equal CR in 4E is a solo, for example. You can actively plan for skill challenges.
The OGL brought so much goodness in the way of Third Party Modules. I will never understand why WoTC decided to hamstring something that did so much good for RPGs in general and made D20, and by extension DnD so popular.
See, initially the leading 3rd party providers were waiting for the GSL, and waiting and waiting, and then the first version was very restricting to established companies with employees and had no real guarantees, and ultimately they all jumped ship, developed their own stuff, and are currently riding some very successful waves. I think the main reason we don't have 3rd party 4e support has less to do with the current GSL, though, and more to do with the lack of developers and design teams not dedicated to some other game.
And a lot of the reason for this was due to WoTC dragging their feet and then finally pushing out the unpopular 4E GSL. The 3rd party companies had to make a hard decision. And now, WoTC has created their own greatest competitor who had previously been their biggest feeder (Paizo). Some people might blame the OGL for Paizo, but we have to remember, Paizo used to get people to buy 3e's splat and crunch books. And now....Pandora's box is open. These companies have proven they don't need WotC anymore. They have an established fanbase. Why make stuff for 4e when a 3rd party can just make their stuff for Pathfinder under the old OGL. It makes more financial sense.
Another 3rd Party 4E Rennaisance is certainly possible, but I just don't see it as very likely given that OGL still exists and has a lot of support by other 3rd parties and fans. I hope I'm wrong....I really enjoy 4E. I really feel like WoTC shot themselves in the foot with how they handled 3rd parties this gen.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.