Please help us stalk newbies! http://commons.wikimedia.org/wiki/User:Orgullobot/Welcome_log
When they are new is our best chance to catch them and correct their mistakes, before they upload 200 images under a wrong license and no categories... these are the two most important mistakes. Uploading stuff under unacceptable/wrong/no license or no source, and not categorising good images.
Orgullobot automatically welcomes around 50-70 new users per day, who have made at least one edit or upload. EugeneZelenko and I cannot check this many people. As we know it takes 2 seconds to upload a copyvio and 2 months to get rid of it... but the earlier we can catch them the quicker they can be deleted. Be ruthless!
So all you need to do is just check their contribs and if they have made any mistakes, correct them (if you want) and tell them how to correct them and what they did wrong. e.g. post {{please link images}} when they should categorise. Use NSD and {{copyvio}}, tell them there's no originality in screenshots, there's no fair use, use CommonsHelper to transfer images...etc. Once you've done this remove their name from the log.
If, by some miracle, they don't make any mistakes, you may want to congratulate them, or else just move onto the next person. :)
Note YOU DON'T HAVE TO BE AN ADMIN TO DO THIS! You just have to have a decent understanding of what's OK and what's not, and what the correct procedure is.
Hope to see some new eyes on this log soon!
Brianna