Is there a way to see if there are any cars in a particular location? My second question while viewing the site was "is this available near me?" Your eligibility page answered that, as I'm not in the U.S., but if I was, I'd probably still want to know before handing over my Facebook info, and certainly before handing over my driver's license info.
I realize theft risk means you probably don't want to map every car to non-signed-in users like Zipcar can, but something like "number of vehicles within 5/10 km of zip code 90210" would be useful.
In fact, I only found out you're only in California from a discussion/support topic. That seems like something that should go somewhere prominent and upfront.