I was thinking almost exactly the same thing as David: ACS is great toolkit but out-of-the box it doesn't do anything interesting.
One great thing about ACS is that it could fairly easily be extended to have a great out-of-the-box experience that would blow away other toolkits.
Imagine: after initial setup users sees a page with a few links. One liks says: "make it a Slashdot-type site". Other says "make it a wiki", "make it a weblog", "make it a bug-tracking site" etc.
The architecture to support this would be easy to do: main index.tcl is just a dispatch that will redirect to some other page that implements a give "site" based on field in a db. There would have to be some plugin/registration mechanism so that different "sites" can register themselves with the "site dispatcher". When a site gets started for the first time, it would probably have to execute some code (initalized itself). One could even switch between "sites" on the fly. Think of it as "skins" over ACS capabilities.
Unfortunately at this time I fall into "much talking little walking" category. Just wanted to share the idea. I truly believe that having good out-of-the box experience, if well propagandized, could be a big boost to ACS's popoularity. I believe I've read something along those lines at some point on ArsDigita site, this idea is not that original. But it would be a killer demo.
