Unfortunately there is no real "Universal Inbox" for Outlook 2007 or 2010. You can opt to have all mail delivered to a single store, but if you're directing new mail to that many folders then that's probably the opposite of what you want (and it doesn't even work for IMAP and Exchange accounts).

The best I can suggest is to add the folders that you receive mail in to your "Favorites" section, so you can at least see the indication of new mail in the folders without the full folder path crowding the Nav pane.

-SW