My first impression was that it was similar to digg.com, and after using it, I stand by that. (The concept is also similar to StumbleUpon.com, although I find that much more invasive than digg or socialbrowse.)
On socialbrowse, after creating a user account, you create a social network of your friends (real and online). Everyone can add new links, 'vote' on them, and add comments. Presumably, you will like what your friends like, and you'll find friends who have similar interests as you do.
For example, someone added a link to socialbrowse about a surgeon twittering from the OR. It showed up on the socialbrowse site feed, along with the number of people who had found it interesting. I read the article, and voted for it.
At this point, socialbrowse is much smaller than digg - so, there is less variety of links, but a greater chance of making an impact on the community. There is one difference, but I can't decide if I like or dislike it yet. Socialbrowse embeds itself into your normal browsing experience moreso than I've found with digg.
After this link about surgeons using Twitter in the OR was posted on socialbrowse, right next to it on cnn.com was a socialbrowse icon. When you mouse over it, it displays some of the socialbrowse information on the link.
This isn't a need-to-have app for me. But, it's a good place to go when I have 5 or 10 minutes to spend browsing.