Another vote for subnotebooks. I am a OneNote fan and I could really live without all the other extras in OneNote if this one feature were present in Evernote. My imports from OneNote become an unmanagable mess without a proper place to put OneNote sections. Tags are useful but they aren't a replacement. If this feature were put in place I'd be buying licenses for Evernote Premium for everyone in my company and uninstalling OneNote!