Professional social networking site LinkedIn is showing signs that it's preparing for an IPO, reports VentureBeat.

The top tier of LinkedIn's management team has undergone a number of changes recently. Co-founders Reid Hoffman and Konstantin Guericke both stepped down in recent months, and others have also left.

Coming in are former executives from Advent Software (Dan Nye), TiVo (Steve Sordello) and a pair from Yahoo (Patrick Crane and Anil Khatri).

LinkedIn was also busy in the last week or so, trumpeting its own successes and announcing other initiatives, such as the release of an API key that allows third-party developers to build LinkedIn-based applications.

The addition of so much established talent, which could ease stock buyer's concerns, and the fact that their compensation will be largely equity-based and not salary, point to an IPO in LinkedIn's not-too-distant future.

That's bolstered by revenue projections of $100 million in the offing. $100 million is a kind of magic number when it comes to IPOs.