Today, I ran into some discrepancies involving Business Units that cost me time and mental energy that really shouldn't be necessary.
1. At the top right, next to the account/portal name, is an indicator of which business unit you're in -- UNLESS you're in the default "account" business unit. There IS an indicator for "All business units." This is backwards at best. And, either way, there needs to be an indicator that you're in a specific business unit for EVERY business unit.
2. On some of the settings panels, there is a "Current view:" field that sometimes allows you to select any business unit (like on Domains and URLs) and sometimes shows you only the current business unit (like on Blogs). This is an inconsistent and terrible user experience.
I'm a developer and between these two items, I spent way too much time and an unnecessary support chat trying to figure out why I couldn't see all my blogs, when the problem was that there was no indicator that I was locked into the "account" business unit.