There are now more than 5 billion mobile phones in use around the globe, according to a study by Swedish telecom Ericsson. To put that into perspective, the world population stands at a little under 6.7 billion, which means there are almost enough mobile phones for every living human.
"In the year 2000, about 730 million people had mobile subscriptions, less than the amount of users in China alone today," Ericsson said.
Ericsson's study counts mobile subscriptions, where "subscriptions" refer to both billed contracts with providers and the pay-as-you-go plans. With some people having more than one subscription (separate plans/phones for work and home, for example), this doesn't mean there are 5 billion people walking around with cell phones.
On a related note, Ericsson says that mobile broadband subscriptions are growing at the same breakneck pace and are expected to reach 3.4 billion by 2015, up from 360 million in 2009.