Aside from no advertising is there anything else useful about it?
That's doubtful. Twitter has been around forever, and advertisemants are rare on Twitter. There are the occasional "promoted" tweets which people pay to show to everyone (which you can ignore or dismiss, you don't get informed, it just pops up on your news feed with the other tweets) and that's about it. Twitter is actually pretty unadvertised, now that I think about it. It's so much more popular, easy to remember, and fun. I've never even heard of Identi.ca until today and doubt it has so much traction so as to be something interesting. (I first joined Twitter in like 2009 before my friends did and it was blah because there was nothing to do, but now it blew up in popularity in my area so it's "the thing" now. I don't think this will happen with Identi.ca. It looks like a side-network, like FunForMobile. You know, one of those that you're not really sure if they're real or not? Like that.
