Updated: OneRiot has raised $7 million in a round of funding—the latest sign that venture capitalists have high hopes for the hot real time search market. OneRiot indexes links users share on Twitter, Digg, and other social networking sites. It faces stiff competition from a number of other VC backed real-time search companies, including Collecta, which has raised $2 million, and Topsy, which is backed with more than $15 million in funding. Twitter too has indicated it will beef up it own search service in order to crawl pages that users link to, and Google (NSDQ: GOOG) is also reportedly readying its own entry into the market.

New funding comes from existing investors Appian Ventures, Commonwealth Capital Ventures, and Spark Capital. The company says it will use the cash to “enhance its core search product and to support its fast-growing partner network.” Earlier this year, Microsoft (NSDQ: MSFT) released a OneRiot add-on for Internet Explorer 8.

OneRiot was initially founded as Me.dium and offered a browser plug-in that connected web users. As Me.dium, it raised $15 million in a second round two years ago led by Commonwealth Venture Partners.

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