Apple's voice recognition platform on the iPhone 4S is an attempt at creating something that interacts with you like a human. And in fact, Siri may even be more human than people who work at Apple because it looks like she is capable of humility. Apparently if you ask the digital assistant "What is the best smartphone ever?" she will tell you it's the Windows Phone-powered Nokia Lumia 900.
The irony is awesome, but of course the response is based on a quantified interpretation of the question. Siri computes the question as figuring out the "best mobile phones" and by default sorts that list by "customer review average." At the present moment, the Lumia 900 happens to have a 5-star average customer rating. The exact location of this data remains largely unknown, but it does pull from Best Buy's website as a background source.
And of course, since the Lumia 900 hasn't been a commercial blockbuster, there are not as many customers to review it, meaning it's much easier for that phone to get a 5-star average than something as incredibly well-selling as the iPhone 4S. Nevertheless, it is interesting to see the juxtaposition of Siri telling users that something other than the phone they're currently using is the "best mobile phone."