Based on my last post I got some questions on that status of LMS's. Some of my information is a little dated, but here is what I can bring up-to-date.
1. Aspen: SumTotal has several LMS offerings including "Docent", "Voyager", and "Aspen". Of these, I have only seen that "Aspen" has the interactions and objectives support.
2. IBM: Yes, they keep changing names. The last time I saw things with their system was about 2 years ago. I think what I saw later became Lotus Learning Space, but this is conjecture.
3. Oracle: The Oracle iLearning, which is now "OLM" would be the most complete offering to look at from Oracle. I only recommend Oracle for companies that already have other Oracle financial systems already installed. As with any LMS, the cost of the LMS is only a small fraction of the total cost of ownership. The bulk of the cost is the integration of the LMS's database with any existing personnel system. If Oracle is already available at the organization, then adding their LMS is cost-effective. My experience with the other systems you mentioned that are now owned by Oracle is that their data support for the eLearning standards were minimal at best.
I have seen many other LMSs (including other "big" ones) that were purposely omitted from my list because they do not support for interactions and objectives. In some cases, delivering interactions even caused the LMSs to throw exceptions. Unfortunately this occurred on some well known brand-name LMSs.
As you observed, the "big" LMS vendors seem to have less to offer than some of the smaller ones. My experience has been that some of the smaller ones have much better technical support, better technical implementation, and better customer support. Among the big ones, Oracle impressed me, but that was at least 3 years ago. For those of you who would like to know my qualifications to make these statements, I work on the LMS integration for ReadyGo. We have an authoring tool that creates AICC or SCORM conformant packages. In the course of doing this, we have integrated with dozens and dozens of LMSs. What we have seen is that each LMS has their own interpretation of the specifications, especially with AICC. With SCORM, there are fewer interpretations, but there are still behaviors and limitations imposed in the LMS that can affect the learner experience. We have made ReadyGo open enough that it is possible for us to create "LMS-packs". These are analogous to printer drivers. When you go to generate (print) your course, you can choose what LMS or specification you want it to work with like you would choose a printer. This allows the course to report as much information as possible to the LMS without causing the LMS to interfere with the learning experience. For example, some LMSs are set up so that once the student completes the course, they are not allowed to take it again. When customers don't like the one-time-only use of courses, we can set up the LMS-pack so that the course never reports a completion status. Then, the LMS doesn't block the learner from re-using the content. The learning level of the student could be passed, for example, through the score. So that is why I feel that I can provide my opinions on LMSs.
My greatest frustration has been that most LMSs and, as a result, most authoring tools have gone for the minimum necessary to be able to put "SCORM Conformant" on their sales brochures. You can see this when the authoring tool only offers one "AICC" and/or one "SCORM" output option. Course developers have then had to rearrange their courses or just forget about tracking anything more than course completion. This has crippled the true capability of SCORM and AICC, and has resulted in "junk food" courseware as the norm.