Mark, while email verification helps the situation, many spammers can still get through (I know this from experience). I completely agree with the concept of "easy registration". This is one of the many reasons I proposed a
passphrase method. Not only will this stop bots, but it will allow real people to get through very easily.
The question could be extremely simple like "type the word 'fun'" which is really easy for a real person to get through, and very hard for a bot! Now that's what I call an ideal situation. Anyways I attached a zip file for the community builder version (the code is old, so not sure if it works on the latest version of CB). I supplied the file in case it helps the stacked team with a EasySocial version, I'm by no means a PHP developer.