According to a piece in Private Equity Week, the founder of Flock — the browser filled with Web 2.0 goodness wrapped around a chewy Mozilla center — has decided to leave and “pursue other opportunities.” According to the mag, Bart Decrem says that he is looking to move on and build another company, but that his sudden departure (in PE Week’s words) “isn’t tied to anything wrong with the company.” He will remain as chairman and a shareholder.

Valleywag isn’t the only one to smell a rat. Why would the founder move on and say he wants to build another company? He’s not even finished building the first one yet, for chrissake. It’s not as if Flock has become a massively successful enterprise and he can move on to bigger and better things — there’s still plenty of debate about whether there’s any point in developing another browser with Flickr and blog integration, since Firefox is so extensible. I like Flock, but it seems like a bunch of features tied together and disguised as a product.

A quote from Bessemer Venture Partners makes it sound like they need someone with talents Bart doesn’t have. Says general partner David Cowan:

This development has been anticipated since the day we started the company, and if it’s happening sooner than anyone expected, it’s only because of the traction we’re getting with partners that taxes the team for experience and resources.

Here’s Bart’s bio. He’s the former head of marketing and business affairs for the Mozilla foundation, and before that was involved with Eazel, a Linux desktop project. Pete Cashmore at Mashable wrote favourably about one of Flock’s recent initiatives: a private label version of its browser released in partnership with the photo-sharing site Photobucket.