Who next? Warren Buffet? Bill Clinton? Bono?

WisdomTree Investments named former Securities and Exchange Commission (SEC) chairman Arthur Levitt as senior advisor, adding to a payroll that already includes the likes of Stocks for the Long Run author Jeremy Siegel and hedge fund investing legend Michael Steinhardt.

For a fund company with just $400 million dollars in assets under management, WisdomTree has pulled together a truly incredible list of talent, stocking their front and back offices with a who's who of the investing and exchange-traded fund (ETF) universe.  The group includes President and COO Bruce Lavine, who joined WisdomTree after leading Barclays Global Investors' (BGI's) ETF effort in Europe, and deputy chief counsel Richard Morris, who was the head legal counsel at BGI and played the central role in setting up the legal framework for BGI's ETF expansion.

It's not entirely clear what role Levitt will play at WisdomTree. The company says he will "work with management on key industry issues and assist in raising public awareness of WisdomTree's dividend-oriented investment approach."

Whatever his day-to-day responsibilities may be, Levitt will bring a great deal of credibility to the table as an investor advocate. He was the longest serving SEC chairman in history, and was known for his work to increase transparency, improve investor education and generally level the playing field for small fry investors.

"Arthur Levitt is one of the great advocates of retail and institutional investors. As a major proponent of greater market transparency and investor education, he has made a unique contribution toward making the U.S. securities markets among the best in the world," said Jonathan Steinberg, chief executive officer of WisdomTree

Levitt's decision to join WisdomTree will also serve as validation in many people's minds of both ETFs in general and WisdomTree's dividend-weighted strategy in particular. Consider his hiring statement:

"I am pleased to serve as an advisor to a firm that is committed to serving investors with a well-reasoned investment strategy that is packaged in an investor-friendly structure," Levitt said.  "ETFs are transparent, tax-efficient and often cost less to own than traditional mutual funds."

The choice of words is worthing noting: Levitt calls WisdomTree's dividend-weighted approach "a well-reasoned investment strategy."  That falls well short of the bluster we usually hear from WisdomTree management; Steinberg famously said that WisdomTree had "the potential to change the way investors think about indexing and investing."  In comparison, "[a] well reasoned investment strategy" is ... well ... a well-reasoned description of what WisdomTree is trying to do.  We wouldn't expect anything less from Mr. Levitt.

For an interesting perspective, check out this classic interview between Levitt and IndexUniverse.com publisher Jim Wiandt.