Twitter's new look won't be limited to the redesigned Twitter home page. Doug Bowman, creative director at the social media company, posted a screen shot of a refreshed design for Twitter Thursday, according to SocialTimes. Of course, the whole screen isn't even shown because, as Bowman wrote in a comment, "Working on what may end up a significant redesign. Not final yet. What we can show without giving away the farm."

It looks like quite a bit is going to change, and as usual, even the smallest of updates could carry a significant revenue implication for Twitter. Here are four implications of a screen redesign for Twitter (and, more important, its investors):

Twitter may say that a new, redesigned home page reflects an attempt to provide more immediate visibility into what's happening on Twitter... but it's really a revenue play.

The new home page does a great job of providing the information hooks that would get a prospective user to click to learn more and ultimately open an account. Its clear objective is to increase the user base, a challenge that Twitter faced in the second half of 2009, after experiencing explosive growth in the two preceding quarters.

More users means more traffic. More traffic means more revenue.

Revenue hasn't been as fast to change as end-user sentiment, but all that looks like it's coming to an end next year. Social networking site Facebook, which passed 350 million users last month, is poised to move ahead of rival MySpace in ad revenue in 2010, according to a report from eMarketer. The research firm expects Facebook to rake in $605 million in ad spend next year, compared to $385 million for MySpace, which is a News Corp. (NWS) property.

According to Debra Aho Williamson, senior analyst at eMarketer and author of Social Network Ad Spending: 2010 Outlook, "As more marketers incorporate social networks in their business, they will no longer look at them as siloed destinations. Instead, they will look to increase the impact of their social network presence by linking it to other marketing initiatives, both online and offline."

It was only a matter of time. This week, social media platforms Twitter and LinkedIn announced new features that will undoubtedly appeal to corporate marketing departments, so Facebook hopped on the bandwagon. Its new preferred developer program is a step toward structuring the Facebook application development and services space, by endorsing providers known to the company.

The program is still in its infancy, which means there isn't much structure around it. According to AllFacebook, "[T]here's really no way to apply to be in the directory aside from being connected with the people over at Facebook." Fourteen vendors are already listed in the directory.