Last year, I used to aggregate update sites with the Buckminster Aggregator, but since that won't install into Eclipse 3.6 (Helios), I had to migrate to the B3 Aggregator. This new version of the Aggregator is greatly expanded and worked fine until recently, when it has begun to suffer from a rather nasty p2 problem: instead of the Director just installing the aggregator into an Eclipse instance prior to then running the aggregation, I get "The copies of profile SDKProfile are not in sync," and the whole process dies. http://www.blogger.com/img/blank.gif
So, in order to find a workaround, I went back to Tycho, and discovered you can merge update sites with little more than two simple files:
Unfortunately the Tycho solution doesn't include the ability to add associate sites to the metadata after generation, but that can simply be done as a downstream step (Tycho can call Ant using the maven-antrun-plugin).