I think we all noticed this when 4e first came out. In the 4e DMG, there was a lot of advice on how to stage and run a good adventure. A lot of that advice amounted to simple concepts like "Don't railroad", "encourage PC choice", and all those other great nuggets that we hear every day on this website.
And yet? The first intro adventure in the DMG is a string of combat encounters, one after the other.
This happens a few more times - Keep on the Shadowfell, for example, or the new Gamma World adventure (there's some nice GM advice, and then the sample adventure ignores a good chunk of it).
I understand why this might be done - to ensure that a limited page count is put to best use, that the designers think fun encounters are the most important part of the game, and so on - but it seems to me a case of "do as I say, not as I do".
In other words, new players reading all this handy advice (and I do believe the 4e DMG to be one of the best DMGs ever written) then get shown a sample adventure "written by the pros". Not really having any idea what is "proper" gaming, which would you follow?
The reason I bring it up is because this wasn't always the case with D&D. The famous 1e sample dungeon (the ruined monastery) wasn't a great adventure, but it had choices (and let the GM fill in blanks! Great idea!). Every BECMI intro I can think of was far from great, but they at least had non-linear exploration options (and also allowed the GM to expand upon the dungeon, even going so far as to provide advice on how to do so). I don't recall the 3e intro adventure, and I know there wasn't one for 2e (in my mind, a mistake).
In my mind, the intro adventure should have contained:
1. Three encounters - one easy one with a few minions, one "average strength" one that could be made easier if the PCs took advantage of a "trick", and one "hard" encounter, possibly against an elite boss. One of these encounters should contain a trap that a character with thievery can bypass (and maybe even use to his advantage!).
2. A Skill Challenge.
3. Light Exploration.
4. Possibility for expansion.
5. The ability to come at encounters from different angles due to PC choices (and maybe even ways for the PCs to catch enemies by surprise through clever play!).
6. A riddle or a puzzle.
These, by the way, are all things suggested in the DMG's advice. And for those worried about page count, the Draconomicon offers mini-adventures like this, and they take up a relatively small page count ("the ruins of Castle Korvald", a level 5th adventure, takes 8 pages, and this number could easily be reduced by maybe a page or two with some clever editing).
It's a general opinion on these boards that, regardless of your views on 4e (I happen to like the basic gist of the system but am annoyed by a few quirks of gameplay), the adventures are generally the weakest link. So the fact that the intro adventures are weak should come as no surprise. However, I've always been of the opinion that an intro adventure really needs to showcase your game and display how the game should ideally be run - and it has to do so in an easy to run fashion to allow beginners to run it.
And the recent intro adventures fail in that regard.
My two cents, of course.