In commenting on the enhanced value iLike can offer its users through the Facebook platform rather than the iLike.com platform, CEO Ali Partovi said:

The #1 way people discover music is through friends, and iLike’s mission is to facilitate that. Facebook enhances this in two key ways: 1) instant personalization. On our dot-com site, each new user needs to tell us their music tastes, invite their friends, and get those friends to tell us their tastes. Whereas on our Facebook site, we already know your tastes, your friends, and their tastes, so we can offer you a personalized experience automatically. 2) Not another social network. People don’t wanna go somewhere separate just for music — they want music to enhance their existing online social life. For example: where would you rather see a notification that your buddies are going to see Snow Patrol: on a separate music website, or in the Facebook news feed that you’re already checking five times a day?

This last comment was picked up by Matthew Ingram of the Toronto Globe and Mail, who said “not a bad point.”

But I think it’s a point with some real problems. One of the great shortcomings of social network sites as they currently exist is that almost all of them offer you only one kind of friend. It’s binary — you’re a friend or you aren’t. Now there are some shades of grey on some sites: Flickr lets you call people friends, family or contacts and restrict content shared accordingly; Facebook lets you limit what some friends see and limit how much you see about some friends. But no social network site offers anywhere near the shades of gray that characterize real life friendship.

So let’s think for a minute about music and friendship. Once upon a time, back in the carefree days of youth before career and family came to shape my life above all other forces, my friendship group and my pop culture taste group were one and the same. My friends were my friends because they listened to the same bands I did, or at least their interests were close enough. If there had been Facebook back then, I’d be with Partovi all the way — yeah, combine them, why keep it separate?

But it’s not that way anymore. My Facebook friends are almost all people I know face-to-face as well. The few that aren’t are those who are either friends of friends (in a get together off line and have fun sense of the term) or people with common career interests to my own that I’ve had interesting interactions with. Am I interested in their musical taste? Well, as a matter of curiosity, but I have no reason to think there’s going to be any overlap in tastes, and no real compelling reason to care if a friend who I love hanging out with at conferences is going to see Snow Patrol. I certainly don’t want these people to serve as a primary source of music recommendations and I may be delighted when they listen to my last.fm radio stream and like it, but I certainly don’t expect them to care about my musical tastes. Yes, it’s cool in those moments when I discover, for example, that Jason Mittell not only has overlapping intellectual curiousities, but a lot of overlapping musical taste too, but that’s the exception.

In contrast, I have met very few of my Last.fm friends. Most of them I imagine I’d have very little to say to if we were to meet. On the other hand, I can have rewarding interactions with them about music, and in many cases, their musical tastes are of great interest to me.

I would be happy to have my Facebook friends as part of my Last.fm friendship network, but I would never want my Last.fm friends subsumed within my Facebook network.

The short point here is that as long as we are limited to a friend vs not friend way of categorizing people, there are tremendous benefits to keeping “friends” separate on separate sites. I agree people don’t want multiple social networking sites, but until we are given meaningful ways to categorize friends within social networking sites, those of us who have online ‘friends’ of very different sorts need them.

There’s a lot of research out there about the many dynamics of relationship grouped together within the broad concept of friendship, and people developing social network sites would be wise to familiarize themselves with it and offer richer relational categorizing choices. But so long as a social network ‘friend’ is an either/or relationship, banking on the convergence of all such sites is profoundly limiting.

In particular, I suspect it is limiting the happy user base to teenagers and other young people who are most likely to have one sort of identity around which their friendships revolve (though it’s still important not to oversimplify teenage friendships). But those of us who, for better or worse, have come to have more bifurcated selves with different friendships that accompany each, and very few that span them all, are important too. There are many more of us, and all those teens are going to turn into us. Right now social network sites are used primarily by teens, but that doesn’t mean it’s going to stay that way. Older folks need music social networking sites much more than teens do for this very reason — we are much less likely have peers who we can rely on to turn us on to new music. And we’re the ones with tons o’ cash to drop on music purchases.