Several times I've started writing a contribution to this topic, but I've deleted it each time. Many of the things I've considered saying have been expressed here already by others.
Plenty of recording artists remain interested in making ambient music, and plenty of listeners remain interested in listening to it. Many things have changed about how those artists record and release their work, and many things have changed about how listeners obtain sounds they can listen to.
When I observe "Things sure have changed during my time," I'm not sure whether I track myself back to when I started working on Hypnos in 1996, or when my own listening shifted over to almost 100% ambient/electronic in the earlier 90s. I probably wouldn't go back before that, to listening to Klaus Schulze and Eno and Jarre in college, because I had no sense of any kind of "scene" or any knowledge of other fans, or reviewers or radio shows.
Somewhere in the 90s I started to discern an actual "scene," or a group of listeners, reviewers, and music-makers overlapping in their listening and reading and discussion... between rec.music.ambient and rec.music.newage and ND magazine, Option magazine, i/e magazine, Wind and Wire, Deep Listenings, Outburn, New Age Voice, Dreams Word, and a variety of early webzines like the AmbiEntrance and Ujamaa's Ambient Experience, as well as many informal reviewers (many people actually took this somewhat seriously back then) on the firstname.lastname@example.org
The most talked-about recordings were released on labels such as Hearts of Space (and their excellent "dark ambient" imprint Fathom), Silent, Emit, Multimood, Extreme, Side Effects, Linden, Raum312, EarRational, Asphodel, Barooni, Amplexus, Mirage/Oasis, Charrm, Manifold, Tone Casualties, Beyond, R&S/Apollo.
Pretty close to 100% of those labels and periodicals are gone now.
So, the ambient scene as it was before could be considered dead and gone, except that many of the people who were creating and listening to the music then are still doing so. Also there are many new listeners, zillions of new music-makers, and even a few new record labels and music outlets that didn't exist in the mid-90s. I recognize many of the individuals who post on this forum from the old rec.music.ambient and rec.music.newage threads, and the banter on the ambient@hyperreal mailing list. Just this morning, Stephen Fruitman posted a mini-review to the hyperreal list and I though to to myself, he's probably been doing that off-and-on for fifteen years!
The above should not be mistaken as an assertion that everything is thriving. Thriving music scenes don't see three music reviewers stop writing reviews for every one new music reviewer to come along. If the ambient scene were really thriving, you'd see more people starting up periodicals, webzines, mail order companies, download stores, and record labels.
We're stuck somewhere in between dead and thriving, with many signs of weakness, and some impossible to ignore areas of necrotic flesh.
I think blogging and podcasting about ambient music might be the sort of thing that gives listeners, artists and various enthusiasts a sort of common ground, a gathering point, a town square in which to banter and share, to warn others about inferior new releases, and give encouragement where interesting new sounds are made. I'd like to think this Hypnos Forum has served in some way as such a meeting place, but I can't help thinking there's more I could be doing to make it appealing and attractive, so more people are compelled to visit more often. Maybe some of you can share ideas along those lines.
Wherever people care enough to wonder "What's happening to our little scene here?" I'd argue you still have something. It can be a little unnerving when months pass without a worthwhile post to the ambient@hyperreal mailing list, or to realize there are only a few webzines going that are consistently updated and worth reading. But people still keep listening to the music, and others keep making it, and I believe there's still enthusiasm there. It's certainly changed from the times when the number of releases was small enough that an enthusiast could hope to purchase virtually all the noteworthy recordings as they were released, and everyone could discuss, say, the latest O Yuki Conjugate album, or the new Amorphous Androgynous. Now unless it's the newest Steve Roach, it seems you can't find two people who want to discuss it, and most people's "now listening" lists seem either increasingly obscure, or backward-reaching.
I'm a little discouraged in some ways but I also feel there remains enormous opportunity for participants in this scene to make something more out of it.