I updated to Froyo 2.2.1 recently. Yes, I had to hack over my Hungarian unbranded Galaxy S to make it UK, since UK has access to 2.2.1 Froyo firmwares.
Biggest change (from my aspect at least) is ability to sync Calendars from non-primary accounts too.
Problem solved. Cleaned up all the "cross account" access permissions (described in previous post), and all works like a charm.