Use :

(require 'org-export)
(require 'org-e-latex)
(require 'org-e-beamer)

M-x org-e-beamer-mode
(to edit your slides)

and

M-x org-e-beamer-export-to-pdf

to generate the pdf.

Should work with H:3, I'm using it.

Generally speaking, the new exporter seems more reliable than the regular
one
albeit there may be some discrepancies (sometimes, I need to kill my org
buffer and
visit the file again).

Fabrice

2012/9/9 Robert P. J. Day <rpjday@crashcourse.ca>

>   i've puzzled over the manual and can't seem to find the switch to
> give me 3 section levels rather than the 2 i'm getting now.  section
> 11.1 in the manual reads:
>
>