The PR checklist is not the one source of tracking. As you've stated the EMO creates tracking bugs with the project leads in copy.
We automatically copy project leads on the tracking "bugs" that the EMO creates to track various reviews (including release reviews). We also add the committer who initiates the review in copy (usually, this is the committer who submitted the IP Log for review). We selected this mechanism primarily because this allows us to maintain a connection with the project team but also allow others to monitor the progress by adding themselves in CC.
As you noted earlier, you can query Bugzilla for these tracking bugs (here's a
Bugzilla query) to find all of the ongoing reviews for EE4J projects (we follow a very well defined pattern with the subject line on bugs to make them easier to track).
The EMO creates a bug when we get our first hint that a release review is required. Most often, this happens when the project team requests an IP Log review. But we will also create the bug if we notice a project requesting PMC approval or when the project sends a note to EMO requesting that we set them up for a release review.
The PMC approval is not a rubber stamp. It has specific meaning in our implementation of the process. We discussed this during the specification committee meeting last week. The role of the PMC is different from that of the specification committee. This will become more apparent as the projects are unleashed to innovate.
The short version is that the PMC approval is an acknowledgement from the PMC that they believe that the project is correctly implementing the Eclipse Foundation Development Process, that the project continues to operate within their defined scope and the charter of the top level project, and that they believe that the documentation provided for the release review is sufficient to provide context around the release. The EMO depends on the PMC having a tighter relationship with their projects operating under their purview than is possible for EMO and we use the release review as a last chance opportunity to address outstanding concerns and issues.
We use the mailing list for this for a couple of reasons. First, in order to actually send the email, the committer must subscribe to the PMC list, improving the chances that the project team has at least one representative on that list who can represent the interests of the project in future PMC discussion. Second, it gives me some assurances that the PMC are actually paying attention to the projects (not all PMCs are as active as EE4J). Third, the PMC is not just their specification committee representative; since it's unlikely that any one member of the PMC will have familiarity with the comings and goings of every single project, we address the approval request to the entire PMC. Finally, the EMO has limited resources and needs a consistent manner of making all of the above happen for all of our top level projects.
Note that the EMO's practice is to accept a single +1 from any PMC member. We purposefully "drag our feet" for a bit after seeing a first +1 to make sure that other PMC members have a chance to object. And yes, this does happen.
TL;DR: the PMC approval requirement comes from the EMO; it is not a steering committee decision.
Wayne