This video was released in January, but I just saw it:
Falcon Heavy | Flight Animation - YouTube
It shows a reusable version, the 3 cores at least, of the Falcon Heavy.
To estimate how much the cost to orbit can be reduced, SpaceX has quoted a price of $125 million for the Falcon Heavy. Elon Musk has also said the cost of the F9 is about 3/4ths first stage and 1/4 upper stage.
Then to find an estimate for the price of a core on the FH solve:
(3 + 1/3)X =$125,000,000, or X = $125,000,000/(3 + 1/3) = $37,500,000. And the cost of the upper stage would 1/3rd of this to be $12,500,000.
On an "Ask Me Anything" Reddit, Elon suggested the Merlin 1D can do 40 reuses:
Elon Musk
reddit AMA - January 2015
http://interviewly.com/i/elon-musk-jan-2015-reddit
Then the cost for the Falcon Heavy using the 3 cores for 40 uses and the upper stage for 1 use would be:
3*37,500,000/40 + 12,500,000 = $15,300,000. And the cost per kilo for the 53,000 kg payload cross-feed version would be 15,300,000/53,000 = $290 per kilo.
