I purchased Watson today. You should too.
It's sorta like Sherlock for Jaguar, though this belies the fact that Watson preexisted Sherlock for Jaguar. It's faster and has a lot more tools than Sherlock does, and it has an open architecture for making more tools. I like Sherlock's AppleCare, Dictionary, and Yellow Pages tools better, but Watson is, overall, a superior product. Additional features I like: Football Scores tool, TV tool, Google tool, Amazon.com tool, Package tracking tool, Weather tool. There's a lot more, but those are the additional ones I use often.
FWIW, I don't think there's much to the Watson claim that Sherlock stole from them. There are some places where perhaps Sherlock stole from Watson, but most of Watson is based on standard Mac OS X look-and-feel, standard web services, and obvious designs. I love Watson, but a lot of it seemed fairly obvious to me.
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