I think there are some outstanding companies making modules/adventures, and I'll give an example of two that are doing it a different way.
1) Necromancer Games. Great slogan..."3rd Edition Rules, 1st Edition feel". And, for the most part, they've used that as their driving force - making modules that hearken back to the early days, but ones that have been getting progressively better and more ambitious. Add to that the fact that Clark and Bill have a strong online presence and have almost a cult-like following, and they are one of the ones to point to and say "see, it can be done and done correctly". Of course, having WW backing your publishing doesn't hurt, too.
2) Auran. Some of you may or may not have heard of them. But I was astounded at all the goodies you get with their adventures. Full color maps and middle insert drawings. Outstanding artwork. Full blown character sheets for their key NPC's. But best of all is a CD-Rom that has a soundtrack for the adventure, 3-D drawings of some of the key areas that you can show your players, and an entire PDF version of the adventure that you can use to print off player handouts, maps that you want to markup, etc. Their adventures are a tad pricier than most, $20 for a standard 1-2 session adventure. But you know what, the adventures I have, especially "Sanctuary", are damn well worth it in my opinion.
To me this is a riskier but fairly inventive approach that has been dabbled in by other companies in the past, but has not been stuck with. Every D20 Auran adventure that I've seen has these CD's and this outstanding design quality, so they seem committed to this approach. And I say "bravo"! So long as the adventures are entertaining, and so far they have been, I will support them. I encourage everyone to take a good look at "Sanctuary" and see if you agree with me.
Dungeon is an excellent source for adventures, "Rana Mor" is still one of my ALL-TIME favorites of any adventure. But there are other companies producing good stuff, too.