I have worked for aD and have quite a lot of experience with both ACS Java (or ECM, or CCM, or whatever it's called these days) and ACS TCL / OpenACS, and I clearly prefer the latter. Primary reasons for this are that OpenACS has a live open source community, allows for more rapid development than ACS Java, and is vastly simpler to understand architecture wise and to modify to your needs. I suggest that you take a look at
dotLRN and our
dotWRK demo server, which Lars threw together in like an afternoon to show what dotLRN might look like when used by a company.
I agree that the look and feel of the ECM screenshot is very nice and I could well imagine changing some templates to make dotLRN look like that.
