Facebook is said to be testing a new, ad-friendly homepage design. (ROBERT GALBRAITH/REUTERS)

Inside Facebook set off some buzz with its Thursday report that the social network is testing a new homepage that will make ads visible at all times.

The unofficial Facebook news blog said that the new design would keep ads, the navigation bar and side app bar static while users scroll through news feeds.

This kind of design, if implemented, could make it easier to navigate through the site, but it would also help advertisers by keeping their ads in front of users for longer periods of time.

Companies aggressively market themselves on Facebook — a recent study from EMarketer found it’s poised to top Yahoo as the top display ad-selling company in the U.S. — but how much does one fan really affect a business?

According to a new study from analytics group Experian Hitwise UK, quite a bit. The firm looked at the return on investment companies get from advertising on Facebook and found that one Facebook fan equals roughly twenty extra visits to a Web site per year.

In previous studies, Facebook, with its several options for sharing information, appears to be a more effective marketing tool than Twitter. In March, Mashable researcher Vadim Lavrushik found that a post on Facebook received 3.31 clicks on likes, shares, comments and links, while a Tweet got about .38 clicks per tweet.

“A Facebook action gets roughly 8.7x more clicks than a tweet,” he concluded.

Are you more likely to follow-up on information from Facebook or Twitter? Let us know in the comments.

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