Most prominent among the critical voices is Chris Messina. Messina designed the Get Firefox ad that ran full page in the NYT years ago, kicking off that browser's adoption, co-founded the BarCamp global network of tech conferences, is on the OpenID Foundation Board and he's the leading mind behind the emerging Activity Streams data standard. All the big social media vendors listen up when he speaks about the web and yesterday he spoke loudly about Facebook vanity URLs.

Messina cites three other thinkers in his critique:

• Vanity URLs as anonymity. Messina: "If Dustin Moskovitz were dead, he'd be rolling over in his grave. For those of you who don't know who Dustin Moskovitz is, he's one of those infrequently mentioned co-founders of Facebook that prevented Facebook from offering usernames or friendly web addresses (so-called "vanity URLs" in the industry) from the beginning. It was his insistence that people should go by their real names on Facebook -- and should thus perform under their true identities -- that I posit has accounted for much of Facebook's success with non-digital natives."


• Vanity URLs as too much power for the vendor. Brian Oberkirch, after SXSW this year: "At one of the SXSW panels a few weeks ago, I saw something that caught my eye. I think Micah may have started it, but one by one all the panelists took their name placards, wrote their Twitter handles on the back, then flipped them around so you were looking at a row of people announcing themselves by @handles....Think of the power of this for Twitter. You don't need to name the animals. You only need to be the language in which animals speak [about] themselves. For Unlimited Power (mmmwhahahahhaha)"


• Vanity URLs as lock-in for users. Messina: "[This is something] Tim O'Reilly warned about in his definition of Web 2.0. He said that one of the new kinds of lock-in in the era of [cloud computing] will be owning a namespace. There you have it -- who are you going to trust to own yours?"

Think about how often many people now identify themselves as "@twitterusername" - is that not a little creepy? The more we build our identities, social connections and personal histories around a single communication platform that we don't control - the less free we become to take our ball and go home if the need arises in the future.

What if Twitter does something more egregious than its recent muffling of conversation via @ replies? What if Facebook does something you find incredibly offensive regarding matters like Holocaust denial. What if a better service simply comes along? What are you going to do - leave Facebook?

That will be hard enough given that all your messages, your media and your friend connections are trapped there. Why make it harder on yourself to act freely by introducing yourself as Facebook.com/ImAgOober to everyone you meet?

So goes the argument. It's better to grab your own domain (I have Marshallk.com, for example, and wrote about this there as well) and to use that link to then point people out to whatever social networks you happen to be participating in at the time. You'll always own your own domain and you set the rules.

Perhaps this is all a bunch of conspiracy theory, though. Perhaps most people don't care because our "digital identities" and the data we produce and share isn't really that important to us. Maybe we're more than willing to sell that stuff to Facebook for convenience and the social connections we have on the site right now. Millions of people referred to themselves as MySpace.com/PersonOrBandName and did that kill anyone? No big deal. That could very well be how most of Facebook's 200 million users feel about it.

Sure, we'll all probably go grab our names on Facebook on Friday - but the real question is how we will relate to that URL.