Facebook, MySpace, Twitter, LinkedIn, and other such sites are – in general, anyway – doing quite well on a global basis, according to new stats from Nielsen. Nielsen revealed this afternoon that people all over the world are dedicating a lot more time to social networks.

A report stated, “On average, global web users across 10 countries spent roughly five and a half hours on social networks in February 2010, up more than two hours from the same time last year.” Italians and Australians actually took the lead, too, beating the U.S. average of 6 hours and 3 minutes by 25 minutes and 22 minutes, respectively.

Then here are a couple more interesting findings: “Overall, the active unique audience to social networks grew nearly 30%, from 244.2M to 314.5M in the last year. In the U.S., the average active unique audience grew to 149.M from 115M in February 2009″ (which also works out to 30 percent).

Time Spent On Social Networks Up 60%

Facebook made Nielsen’s last points of comparison anything but close calls, though. It beat the other social networks by wide margins in terms of “% Reach of Active Social Users,” “Sessions per Person,” and “Time per Person.”

Facebook, then, would appear best positioned to find advertisers and generate revenue outside the U.S.

Although the “thud” wasn’t verified until this afternoon, it seems that an online giant fell a couple of days ago. According to new data from Hitwise, Facebook managed to beat Google in terms of visits between March 7th and March 13th, becoming the most visited website in the U.S. for the week.

The graph visible below makes the changeup pretty clear (blame the sloppy enlarged bit on us, not Hitwise). What’s more, it doesn’t look like Facebook’s going to relinquish its lead anytime soon.

Facebook Unseats Google As Most-Visited Site

Heather Dougherty explained, “The market share of visits to Facebook.com increased 185% last week as compared to the same week in 2009, while visits to Google.com increased 9% during the same time frame.”

Then here’s one more interesting fact, courtesy of Dougherty: “Together Facebook.com and Google.com accounted for 14% of all US Internet visits last week.”

Anyway, this development represents a major win for Facebook. The ability to represent the social network as the number one site should count for a lot as corporate representatives talk to advertisers and investors, and could result in a direct boost in revenue. A further snowball effect in terms of user interest might occur, too, since most people like to be part of something that’s popular.

It’s been a pretty big week for Facebook. Not only is there a lot of talk about Facebook’s potential for becoming the top news source on the web, but the company celebrated its sixth birthday, is passing the 400 million user mark, and began rolling out some new design changes. In addition, the company is said to be rewriting its messaging feature and preparing to launch a webmail product, but first things first.

The Birthday and 400 Million Users

Facebook CEO Mark Zuckerberg discussed it in a blog post last night. “Today we’re celebrating our sixth birthday, and this week there will be 400 million people on Facebook. Just one year ago we served less than half as many people, and thanks to you we’ve made great progress over the last year towards making the world more open and connected.”

“Facebook began six years ago today as a product that my roommates and I built to help people around us connect easily, share information and understand one another better.” he added. “We hoped Facebook would improve people’s lives in important ways. So it’s rewarding to see that as Facebook has grown, people around the world are using the service to share information about events big and small and to stay connected to everyone they care about.”

Facebook hosted a celebration and announced some releases at the Facebook headquarters last night. This was followed by a hackathon where Facebook staff stayed up all night coding and building new ideas for products.

Design Changes

Facebook announced some new changes to the design of its homepage. Users can find their newest notifications, requests, and messages in the top menu. When a user receives a notification, they will see a red bubble appear in the left-hand corner by the search bar. When the icon is clicked, a drop-down menu appears with the most recent notifications. The Home/Profile links are in the top-right corner with the Account menu, which includes privacy settings and the log out link.

Facebook Notifications

The menu on the left-hand side of the screen has been completely reworked. “The left menu has been organized to make it easier for you to communicate with and discover content from your friends. You can now access your messages and other core features all in one place, to the left of your News Feed,” says Facebook’s Jing Chen. “With the Photos dashboard you can browse recent photos of your friends, and the Events dashboard lists your upcoming events along with events your friends are attending. The Friends dashboard will help you find friends, see which of your friends have recently updated their profiles and filter your News Feed by Friend Lists you may have already created.”

Chat has also been made more prominent with a list of online friends displayed on the left. The new apps and games dashboards, which have been discussed lately, can be accessed from the menu as well. The dashboards feature personalized updates from the apps, and they have launched with new privacy settings.

The changes are still rolling out, so it’s possible that you do not have them yet, but you will soon enough.

The Webmail Product

Michael Arrington is reporting that a “source with knowledge of the product” says Facebook is launching a webmail product. If MySpace can do it, surely Facebook can too. It’s being referred to right now as “Project Titan”, although the name will likely change.

Facebook’s messages as they stand right now, lend to email notifications. When you check your email, you find that someone has sent you a message on Facebook. If Facebook gets you using its own email service, it’s cutting out the middle man, and that means…you guessed it – more time spent on Facebook.

Facebook As the Web’s Top News Source?

I’ve already written on this topic this week, but basically, the more time people spend on Facebook, the more convenient they may find it to simply get their news feeds there. If Facebook enters the email game, that’s only going to get people using Facebook that much more, and even open up yet another way for them to get their news on Facebook, through email newsletters and news alerts.

Update: Microsoft has announced some changes to its partnership with Facebook. Facebook will now be taking over its own display advertising, and will get a more feature-rich version of Bing search for its web search.