From a technical point of view, it has proven to work remarkably well, even if some implementations have run into the infamous cross-domain scripting problem. For an outline of the issue, and a growing number of solutions, here's an article we did earlier. It should be borne in mind that the IEEE version of the API contains a number of fixes and harmonisations, so is not exactly the same as the ones used in SCORM 1.2.
With the IEEE Standard Association's blessing of the API, the total number of IEEE Learning Technology Standards Committee (LTSC)' standards notches up to three: the Learning Object Metadata (LOM) standard has been out for nearly a year and the Learning Technology Systems Architecture (LTSA) came out just before the summer.
One part of the SCORM that is not yet included in the roster is the IMS Content Packaging specification; the bit that literaly wraps it all up. Following the transfer of the -unrelated- IMS Reusable Definition of Competency or Educational Objective (RDCEO) spec to IEEE LTSC for standardisation, Content Packaging may follow soon. Discussions in last week's IMS quarterly meeting in San Jose certainly point in that general direction.
More information on the new standard can be found on the IEEE LTSC CMI Working Group's page on the revamped IEEE LTSC website.