That question might seem more relevant to Hydrapinion's Carry section than Mac, but with renewed talk (sorry!) that Siri might turn up on Mac OS X (eg, OSXDaily) and Apple's currently hypothetical next-generation TV product, I claim dibs on the topic.

Ars Technica looked at the data consumption associated with a selection of Siri requests, and found an average of 37KB for 'local' tasks such as "Make an appointment for 2pm on Friday", and 95KB for those that retrieved information from the Internet, eg "How many calories in a muffin?"

On that basis, Ars concludes that if you performed the same queries every day, that's about 20MB per month. A straw poll suggested most Siri users make fewer queries than that, so it shouldn't be a big deal unless you're already running close to your 3G data quota.

But how often would you use Siri is it was available on your Mac or TV? If you're like me and spend much of a normal working day in front of a Mac, I suspect it could be quite a lot, but it depends on the environment you're in. After all, in a shared office you wouldn't want to tell Siri to call your phone betting account or open a NSFW web site - not that you should be doing either, but you get the idea. Some tasks just aren't appropriate for voice control.

And at the risk of entering Play territory, Australians reportedly watch TV for an average of around two hours per day. That probably equates to about three voice commands ("Watch channel X" (with an implied "Switch TV on"), "Watch channel Y", "Switch TV off") for live-from-air watching. But I'd imagine that people using a Siri-enabled Apple device are likely to a) watch more TV than average, and b) have more complex setups.

So a more typical day might involve some combination of scheduling PVR (including Foxtel iQ) recordings (I hope the next-gen Apple TV is going to include an IR blaster to control other devices, along with access to Foxtel's EPG), and watching live-from-air (especially news and sports coverage), previous recordings, online content (YouTube, iView, etc), and paid on-demand movies and TV shows (eg from the iTunes Store). Not to mention flipping the TV across to a games console or an iPad or iPhone.

Regardless of the additional commands In that sort of environment, the amount of data used by Siri pales beside that drained from your quota by video consumption.

Given that most of Siri's work is done by a server, I wouldn't have thought it would be too difficult to add it to products other than the iPhone. Maybe there's more to Apple's giant North Carolina data centre than just iCloud?