Excellent documentation. I've used your blog, the upgrade guide, and a few other resources.
One point that I would add for others upgrading: check the event log after each server that is upgraded. Do NOT proceed until you receieve a 1210 event within the Operations Manager event log (except for a clustered RMS, which you can proceed with each subsequent node until the cluster upgraded, but do not start any other servers until the final clustered node that will hold the resources presents a 1210 message).
We found that we were getting random Health Service State corruption if this was not finished first.