Absolutely. I do this all the time.
Look at the stuff from Clinton Kitson for the export
http://velemental.com/2012/06/05/importing-and-exporting-vapptemplates-from-ovfs-with-powercli/
I use the Import-CIVappTemplate command to do the imports, although it can be a little buggy for large vapps -- the next release is supposed to contain some optimizations.
-Doug