Companies might also find that the massive job of going through all their existing data and inserting semantic tags is just too daunting a job to tackle, even if it might save time and money somewhere down the line.

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The interest graph combines the click stream, the semantic stream, and the product engagement data to illuminate the path to sales.

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Like the early days of the web, he said, many people were now tagging data with the labels and identifiers demanded by semantic web technology.

BBC: NEWS | Technology | Yahoo makes semantic search shift

These acquisitions include Jambool (a social gaming site), Metaweb (a semantic search engine), and Angstro (a social networking startup that pulls data from Facebook, Twitter, LinkedIn, etc).

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