Reddit has changed to such a degree that plenty of its early users want an alternative that doesn't currently exist. The site is involved in a tug-of-war betwe

Reddit has changed to such a degree that plenty of its early users want an alternative that doesn't currently exist. The site is involved in a tug-of-war between users who want quality news articles and those who want pictures and jokes, with the latter overwhelming the site. It's not hard to imagine a successful competitor appealing to the more mature crowd, especially since Metcalfe's Law does not apply to the same degree with social news sites since a social news site only needs a few hundred active users to be useful. Facebook is very entrenched and difficult to compete with. It's the universal identity directory that the Internet has always needed since the start. Very hard to directly compete. I'm still not sure I completely 'get' Twitter. I think it's used for many purposes, many of which could be eroded by rather different and more specialised services. Its 'spying on celebrities' niche seems pretty entrenched, though.