A few general points about ACES vs Blackboard:
Regarding IMS "compliance," "conformance," or whatever, you
probably already know that no two vendors implement the same
subset of that spec, so it's very hard to compare two platforms
without getting very specific. Michael, you have wisely specified a
(sensible) subset of the standard that you care about; you might
want to look at it on even more fine-grained a level to see which
calls and APIs are implemented within that subset.
At the moment, ACES does not comply with the IMS. However,
since there has been some work to integrate XML capabilities
into AOLServer, I don't imagine it should be too terribly hard to do
what you want to do. (For those interested in reading more about
the "standard," go to http://www.imsproject.org.)
Regarding the assessment engine, the tool currently in ACES is
survey-simple, which is completely inadequate as a testing tool.
Blackboard's testing tool is, well, adequate, but not great. There
is fairly strong interest within the ACES user community in
porting the survey builder module--an extremely powerful tool
which, as far as I can tell, aD never quite finished. based on the
ASJ article they have written about it, such a tool would blow the
other test engines (including those in Blackboard and WebCT)
out of the water.
Frankly, I think item number four on your list--"virtual
classroom"--is dangerously underspecified and possibly
underweighted. After all, the main point of these systems is to
provide a teaching environment, i.e., a virtual classroom. Just
saying, "Oh yeah, we have one of those" isn't going to tell you
whether teachers and students will actually use it and be happy
with it. You need to break down the features of the virtual
classroom, as well as the potential for easy customization and,
perhaps most importantly, the quality and adaptability of the user
interface.
