I've noticed an inconsistency in the way keyword fields are handled in Web portal. I was helping a new user today, and this inconsistency really tripped her up.
In the Article Properties > Article Metadata screen, when you add a keyword or internal keyword, after you type the keyword you can either hit the tab key or the return key to "apply" the keyword.
But in Layout Templates Beta > Mapping, when you edit a mapping rule, and you type a keyword or internal keyword, hitting the tab key has no effect. The keyword sits on the line and allows you to move to the next field, but it isn't "applied" until you hit the return key. This caused the user to think she had entered the keyword, when in fact she hadn't. Caused about 25 minutes of troubleshooting until we figured out what was going on.