Setting org-export-headline-levels depending on export backend

[Rafael]

I would like to have an org document export nicely (including some
subtleties like theorems) to a latex document and to a beamer
presentation. I have been mostly successful using filters, but it would
help me a lot if there was some way to declare to use the #+option H:2
when exporting to beamer, and H:3 when exporting to latex. Thoughts?