I agree with everything I said in the thread Emufarmers linked to.
Seriously, it's meaningless and nothing to worry about. You could be moved from a semi-slow server with 1200 users to an even slower server with 3 users, because one of them refuses to understand that you don't get a dedicated server for $9.95/month.
If you have a really busy site and it's not flying along here, there's a good chance that it's because your site needs to be on a dedicated server--not because of how many other users are on the shared server.
Even if it is okay here, but you see it quickly growing at a rate where it will need a dedicated--I'd just get it over with instead of waiting until you're forced to upgrade.
I think I'll go use up all of my users and not have them do anything. That way, others will see the user count and stay off of my lightly-loaded high-user-count server.
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