Yeah, I don't recall any specific use of that username anywhere important. We create our own usernames for unix logins (ftp, etc).
Regarding the OPs thinking that since their site is up their account must be active, because of the time needed for DNS propagation, you might be looking at your old site. Actually, if you haven't logged in and uploaded content to DreamHost, it's very likely that either DNS hasn't propagated yet or that you're looking at a cached version of your new site.
Have you uploaded your site to DreamHost yet? (this is directed to the OP)
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