Digg has its problems, but Digg clones aren't one.

An early Web 2.0 favorite, social news site Digg has seen lots of competition over the years from sites that do almost exactly what it does: have users submit and vote on their favorite websites and news stories.

AOL launched a clone called Propeller (first called Netscape). Yahoo came out with Yahoo! Buzz. A sad site called Mixx even ripped off Digg's double-consonant name. According to this chart from NeXT Up Research, none of these sites are close to touching Digg in terms of traffic.

But new Digg CEO and founder Kevin Rose -- who forced former CEO Jay Adelson out earlier this year -- can't rest.

While Digg clones aren't a threat, Web behemoths Facebook and Twitter are. Both services now do the what only Digg used to: allow users to share stories and find others based on their popular appeal.

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