"Siri, how much data do you gobble up in a month?"

Apple's new iPhone 4S has been in users' grubby little hands for a bit over two weeks now. One of the main features of the 4S is the virtual "personal assistant" Siri, a technology that Apple acquired in 2010 and integrated into iOS 5 for integration with the iPhone 4S. When we put Siri through its paces during our iPhone 4S review, we came away with a mixture of bemusement and optimism. The service is still in beta and has its rough patches, but it's pretty decent at performing Web searches and other basic phone tasks, such as setting up appointments, making reminders, and text dictation.

But one huge caveat to Siri is that it requires an active Internet connection in order to function. Apple sends Siri voice data up to its own data centers for processing and the sends the results back down to your phone, even if you're only trying to perform a task that shouldn't require any network connectivity. This can sometimes be frustrating when you're in a low-signal area with no WiFi available, but heavy data users were quick to point out that there are even bigger potential downsides to using Siri: it could force you over your monthly data quota with your cell carrier if you're not careful. And in today's heavily data-capped world, such a concern is becoming more and more valid.

Because of this, we decided to find out how much data a typical Siri user might expect to use in an average month. We carefully watched our data usage while performing 11 different queries through Siri, split between local phone tasks and tasks that required lookups from the Internet. We also performed four dictation tasks. Your milage, of course, will vary depending on the kinds of things you might use Siri for and how often you might do those things. With that said, here's what we found.