Just released UsernameCheck.com is a great way to get a quick read on how diligently you have been staking your claim to Web 2.0/Social Marketing properties.
Just go to their site, and enter your desired real name, pen names (or other, sort of "branded" usernames you like to use), company name(s), or even product name(s), and see what is still available on currently 68 services listed.
If you go to the site and enter "alexschleber", you will see that I have been doing my homework over the last year: All but two or three of the "taken" entries belong to me. (By the way, you can also use my list as a template for which services are currently more important than others.)
Here is a partial screen-capture of the results…
Why is this relevant you ask?
Simple: Think of each new service as a new "namespace" (this is a kind of techy term used for programming variables), the idea that there can only be one copy of a distinct name available per such a namespace. So if e.g. WordPress.com offers domains for their members that look like "alexschleber.wordpress.com", or e.g. Twitter uses twitter.com/alexschleber, then you either get that one name or you don’t (same as with regular .com domain names).
If you fail to reserve it for yourself, you may be left with only the less usable "scraps": Names containing hyphens, underscores, and numbers, all of which tend to make things more cumbersome, especially for spelling the name to others via phone or in person.
Secondly, even if you don’t really want to use a given service, if it is of much relevance at all (notice that I have NOT subscribed to every service on Usernamecheck.com’s list), you may still wish to preempt someone else from owning a specific name on that service, who could then turn around and publish or otherwise create information under a that name.
In part, because most of these services, once successful, have a tendency to rank very high up in Google’s (and other serch engines’) search results. So a potential customer, client, investor, or interviewer might have to sort through reams of search listings that may or may not be about you (and that you might have to explain, which is always cumbersome and never helps with that vital first impression).
Now of course if you have a very common name, it is unlikely that you’ll be able to do much about getting it on any of these services. However, at least some of the other spellings with hyphens, etc. may still be available, which is better than nothing if you want to use a given service. However, for your company name or even products you may want to brand/promote separately, you have no excuse to not reserve these.
So, let your great "namespace" land grab of 2008 begin…