Sorry about this spam, Kyle. I don't know why zipperfly didn't reply to his own thread.
I think you misread what I said here but I can see why. Here's what Kyle said:
For example if someone comes to mainsite.com/register/ they can select the option "Yes, I'd like to create a new site" but if they go to subsite.mainsite.com/register/ the option will not be available.
Kyle wanted two different pages. One on the main site that let him allow users to create a site, and one on the subsite that did not.
The plugin does not have that option (one would use wp-signup.php off the mainsite if you wanted that) because this plugin lets users JOIN sites.
Nothing more. Nothing less. No site creation.
You can read http://plugins.trac.wordpress.org/browser/join-my-multisite/trunk/lib/signuppage.php
No create blog options. They have been removed.