Deciding on the best layout. Blog style vs News Site

I’ve had a blog style layout for a long time (a few featured post on top, but basically a long vertical chronology.

It seems that very few sites use this layout any more, rather preferring a CNN-style layout with several different sections viewable and often a great big slideshow style image scroller on the top.

People will say they “like” this or that, but does anyone know of any scientific evidence that suggest any given layout is better than another – especially in terms of pageviews/visit, time spent on site, and other ways to measure people’s interest.

I’m especially curious about the scrolling slideshows that seem to be features of just about every new theme. I find them kind of annoying, but if that’s what people want, maybe I should have one!