To deliver a Notebook for hand-out in important meetings, I typically produce both a landscape and a portrait version of the Notebook, using Aha. and mix & match pages based on the content. This is an extra step I take in Acrobat.
This idea is to be able to specify the page orientation on a section-by-section basis, rather than for the entire PDF.
I also add page #s to the notebook in Acrobat, this would also be a nice option in Aha.
Thank you for your idea. The status of this idea was out of date. Since this was requested we have improved the slide editor to allow you to set orientation slide-by-slide. This will effect specifically how the slide is laid out when the presentation is exported to PDF.