I think the slider control orginates from Panic's Coda web site: http://www.panic.com/coda/ It is a great way to show a lot of content on the same page without vertical scrolling.

This is what we use at http://flow.io and it works well for us. The instant visual feedback is addictive, and a lot of users click the tabs to learn more about our app. Our bounce rate is very very low. Another interesting thing about this control scheme is that users often click the tabs in the intended order (from left to right) so you can reveal what your app does in easily digestible bite-size chunks.