Updated below: Social networking service Plaxo is putting itself up for auction and hoping to fetch up to $100 million, reports NYT. The Mountain View-based company, which was once infamous for the prodigious volume of e-mails it sent out, has tried hard to shed its reputation as a spammer. Originally conceived of as a contact manager, Plaxo has tried to position itself as a neutral third party in the social networking world. Last year it launched Plaxo Pulse, which collects and organizes information from other sites. Plaxo has raised over $20 million from various investors, including Sequoia, Globespan, Ram Shriram and Tim Koogle, notes NYT. It currently claims to have 15 million registered users, though it remains unprofitable.

This wouldn’t be the first time Plaxo has pondered a sale. The site first considered the move two years ago. Both Time Warner (NYSE: TWX) and Yahoo (NSDQ: YHOO) were said to have been interested, according to a WSJ report from last summer. With its new strategy, Plaxo may earn itself a second look from some suitors, particularly with social networking as hot as it is.

Updated: PEHub says the service has received an unsolicited acquisition offer of around $200 million...the company has also has begun informal conversations with other potential partners. The story also refutes the NYT story that the company has hired a bank, and source tells peHUB that no such agreement has been signed.

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