Dare Obasanjo has two great posts with some background and details on Microsoft’s entry into the classified ad service space.  Microsoft’s Fremont (formerly know as Casbah, later to be known as is an atypical classified ad website that allows you to limit viewing to trusted persons in your social network.

Of all of the recent entries into the social networking space, this is one that I think I might actually use, and encourage my friends to use.  I really like the idea of being able to limit my posts, and reading, of ads to trusted or semi-trusted people.

Dare’s post talks about social circles, and tribes based on email and buddy lists.  I think an important part of the success of Fremont is going to be the ability of users to build, manage and share circles that are based on more than just email addresses.  Let me build a circle that includes all of my college classmates that currently live in the Washington D.C. area, or a different circle may include any friend-of-a-friend-of-a-friend.  After I build cool, useful circles, I want to share them with my friends.  That way I could build a circle for a model airplane club, or a Scout troop, and then share it with the members who could then use it to post relevent information or items for sale to the entire circle.  Hrm, seems to have come full-circle to MSN Groups eh?  Merge Groups with Fremont, and now you have a ton of “Special Interest” tribes, ready built, and ready to make use of the new service. Cool…

The major drawback to this social model is that one of the biggest features is based on limiting visibilty of ads.  The only way that Fremont will come out ahead is if Microsoft can build users’ trust high enough that they are willing to post more ads, enough more ads to make up for the limited visibility.  Building more interesting circles will also require that users are willing to include personal details in their profiles. Again, this will come down to trust.

This is going to be interesting.  Microsoft’s ability to integrate this accross Messenger, email, groups, and maybe Spaces is going to make it unique in the field.  Yahoo! can play this game, AOL can play too.  Google is still playing catch-up with their application base, but they’re closing fast.  Whoever makes it easy & seamless wins.