According to the Guardian article that broke the news, "[a] 2005 court ruling judged that cell site location data – the nearest cell tower a phone was connected to – was also transactional data, and so could potentially fall under the scope of the order."[1]
IANAL but it seems clear that cell site data could be included (since it's held to be transactional data), but it would be limited to the towers connected to when making and ending calls, not a complete timeline. [2]
1. http://www.guardian.co.uk/world/2013/jun/06/nsa-phone-record...