Last night I started on "King of the Trollhaunt Warrens", and I do find that the format has improved somewhat over that used in the late 3e adventures. It may be the case that the new, simpler rules for environmental factors take up a lot less space, making the whole easier to read. Or it might be an effect of the new encounter design guidelines.
However, one thing that is very noticable is that the new format is extremely demanding in terms of space. "King of the Trollhaunt Warrens" has a page count of 96 pages (100 if you include the cardboard folder that contains the two booklets and poster map), and spans 25 encounter areas. This is roughly equivalent to the Goodman Games module "Forges of the Mountain King", which has spans 32 pages. And, of course, this is reflected in the costs - $25 for "Trollhaunt Warrens" vs $15 for "Mountain King" despite the economies of scale afforded by WotC's much larger print runs.
(Actually, while composing the rest of this post it occurred to me - "Mountain King" is in black and white, while "Trollhaunt Warrens" is in colour. Naturally, this will have an impact on the price also.)
By way of further comparison, an issue of Pathfinder has 96 pages (a few of which are adverts), and a price point of $20. An issue of Pathfinder is typically comparable to "Trollhaunt Warrens" in terms of support material ("Trollhaunt Warrens" has a number of new monsters, rituals and magic items; the latest Pathfinder had several new monsters, an article on the world's solar system, and an in depth look at one of the major deities in the setting). The Pathfinder adventure, however, covers rather more encounter areas in a lower page count than does "Trollhaunt Warrens".
(Pathfinder also uses a much smaller font than either the WotC or GG adventures, and has considerably less white space. It is also in colour.)
Of course, none of these comparisons say anything about the quality of the products themselves. Personally, the only complaint I would level against any of them is that the Goodman Games module uses the OGL rather than the GSL (necessarily so), and so is forced to use different icons for things than the 4e standard. Considered as adventures, though, all three are very excellent products.
The key question I think this raises, then, is how much are you willing to pay for ease of use? If you want the most adventure for your buck, the older formats clearly have the win. However, the new format definately has the edge in terms of ease of use. (As several people have noted, "Trollhaunt Warrens" could be run almost without preparation; this is not true of either of the other two adventures.)