The final cut of the 9th episode of the Tesla Motors Club Podcast, featuring Chad Schwitters, the former president of Plug In America, is now available. You can watch it now on YouTube or listen to it on all major podcast networks.
2 between the front seats, 2 in center console, 2 in the 3rd row, and I believe 2 in the 6-seater center console if you go for that. Someone also posted a pic of pop out holders coming from the rear of the front center console.
One thing that may have you confused is that two of the front cupholders actually disappear under the (sliding) armrests when not in use. Here's a pic with one slid forward and one slid back: