Joe Kraus–the longtime Silicon Valley entrepreneur who sold his most recent start-up, JotSpot, to Google in 2006 and has been a director of product management since–has moved to its Google Ventures unit as a partner, said several sources.

Sources added that Kraus (pictured above) is likely to be the first of several well-known appointments at the relatively new venture arm of the search giant.

Google (GOOG) announced its VC play in March and said the fund will invest $100 million in “exceptional” start-ups over the next year.

“We’ll be focusing on early stage investments across a diverse range of industries, including consumer Internet, software, clean-tech, bio-tech, health care and, no doubt, other areas we haven’t thought of yet,” Managing Partners Rich Miner and Bill Maris explained in a blog post when Google Ventures debuted. “Central to our effort will be our fellow Googlers, whom we view as a critically important resource to help educate us about potential investments areas and evaluate specific companies.”

Well, that now apparently means Kraus, a serial entrepreneur who co-founded the Web 1.0-era Excite portal and, in Web 2.0, JotSpot, which made wiki-style software for online collaboration.

Currently, only Miner and Maris are listed on the bios page of Google Venture’s online site.

Since the acquisition, Kraus has been leading Google’s OpenSocial efforts to develop standards for social networking platforms.

Please see this disclosure related to me and Google.

While Wetpaint’s $25 million new round of funding was leaked to one and all under embargo until 12:01 am EST today–including BoomTown, so don’t assume any of us report our little hearts out on all these bits of news–what the press release did not disclose, sources said, was an intriguing new investor: Fidelity Investments.

What’s interesting about this wrinkle is that it is yet another validation in the Web 2.0 world from a large traditional institutional investor.

Fidelity, with T. Rowe Price, already plunked down big bucks to invest in widget king Slide in January.

Seattle-based Wetpaint, which allows users to make wikis and social-networking sites easily, has raised about $40 million in total so far. New investor DAG Ventures led the current round, which included investors from two previous rounds (Frazier Technology Ventures, Trinity Ventures and Accel Partners).

BoomTown could not determine exactly how much Fidelity kicked in to Wetpaint in this round, although it did pony up almost half the new $50 million Slide investment.

Wetpaint, which also announced a new embeddable product called Wetpaint Injected today that sounds cool, says it will use the additional funds to goose its collaborative–or as we like to call it: wikified–social publishing platform.