I used to work for a company that had its own voice recognition technology. So we had some researchers that were really into this stuff. They told me that they went to conference where they got to delve deep into TellMe and they were pretty blown away with what they were shown. So I have high hopes.
I think that the stuff that we've seen in the TellMe video where they show what the future of TellMe is supposed to be probably already exists in a lab. They're just looking for the best way to implement it.
As for just voice recognition itself, TellMe is top notch. What you see with stuff like Siri isn't so much about voice recognition, but instead a huge tree of choices that exist in order to narrow down what it thinks you are talking about. It's a huge undertaking, and there's a good reason that Siri came out as a "Beta." MS likely doesn't want to release their version as a Beta. But Apple probably wanted to be first to market.
And if anyone hasn't see the TellMe video for what MS has planned...
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