We wondered why Zipcar CEO Scott Griffith was slated as a keynote presenter at CTIA's MobileCon -- after all, what does renting cars have to do with mobile? Apparently, quite a lot. Griffith stated in his keynote that Zipcar's app and mobile services have taken a much more central role in the organization. The company is developing its own in-car device holder so that customers can hook up their phones for hands-free functions, and more importantly, the Zipcar smartphone app is due for a major update. The current version c
