Mixx is an upcoming social news service. If you're familiar with Digg, Delicious, and Reddit, Mixx takes a little bit from all three to provide a really solid framework for discovering and popularizing Web content.
Much like Digg, Mixx has a front page with user-submitted stories that have been voted up from an upcoming pool. Where Mixx strays (in a good way) from Digg and others is user customization. When signing up with the service, you pick categories and topics you're interested in. From then on, each and every time you check the service, the front page has the top five stories from each of these categories, giving you a quick overview of what's hot on the site. You can actually accomplish the same thing with Digg right now by setting up RSS feeds from each of the topics into a service like Netvibes, or checking out the Digg page on Original Signal, but it's really nice to have this built in.
So what makes this service promising? It's really just a mish-mash of ideas that work well together. Things like a local news section (based on ZIP code), and groups for users to share content with one another give it a social twist that up until last night, Digg didn't really have. So now that it does, what would make a user of other social news services bother making the switch? For one thing, the UI is extremely simplistic and intuitive. Tags are also a really enjoyable way to browse through content--and like Delicious--give submitters a little more control of how their story will show up in site searches, and how other users can find it.
There are a few things that need work though. For one thing, the site is a little sluggish. It's also missing some tools to help you submit content to the site, like a "Mixx This" bookmark that you can add to your browser toolbar, or a shortcut button to add to blogs and Web sites. The comment system is also a little crippled, with no threading, only "@user" replies that note whose comment you're responding to. While I don't think Mixx will ever overtake some of currently popular social news services out there, it could easily build up its own community of loyal users who are seeking more group-oriented bookmarking, and a quick way to eyeball different content genres at once.
We've got 50 invites to give away, so if you're looking to give Mixx a spin (sorry), there's a sign-up form and more shots of the service after the break.
Update: All the invites have been given away. If you missed out, you can still sign-up on Mixx's front page.