@Ron -@James - I see both your points and I agree. And though I'm a stranger to you, you both are very familiar to me and I wouldn't think of challenging your expertise. Your approach will certainly shake things up for the sploggers and spammers. But I don't want to frustrate potential new members expecting to land on a register page and then find themselves trying to figure out what went wrong. For a new user to get a blog on my site is a two step process. The wp-signup.php is modified to only present the "get a user name" portion of the form if the person isn't logged in. And then when they return they will get the remainder of the form to get themselves a blog. They can't sign up for both in one shot. It will also limit them to a defined number of blogs. Then I had to change the displayed texts and email snippets to reflect this as well.

I've already begun a plugin to embed all the wp-signup /wp-activate stuff directly into a WordPress page so I can have a short URL like mysite.com/signup without adding extra to the root directory and keeping it portable if I need to switch themes. And most importantly gain control of how they behave without messing with the core. Heck... I might attempt to merge wp-login into it as well if I have the extra time and feel froggy.

I'm sorry if this reply isn't worded well, my kids aren't allowing me to write it in peace :)
Cheers, Lee