Samsung GALAXY Nexus," you might say into your iPhone only to get a response like, "Don't you mean you want to buy an Apple iPhone?" and take you to the Apple Store to purchase it.
Currently, asking Siri to make an online purchase results in the personal assistant saying, "Sorry, I can't purchase that." With the Wolfram Alpha engine Siri uses, Apple iPhone 4S users can now find out from Siri if a certain product is in stock at Best Buy. An actual purchase however, cannot be completed. Of course, there is no guarantee that the functions described in the patent will ever make it into a version of the Apple iPhone. Still, the possibilities seem so enticing for Apple that it would seem like a sure thing to be included in a future version of the device.
source: FreePatentsOnline via AppleInsider