Userscripts.org

http://userscripts.org/topics/19194

Here explains how to get multiple friends to invite. Look for GNomads post. You do need to add them as a friend, but it is a lot quicker than the add me threads.

After that I used Live HTTP Headers to send invites from the recently added list. I don't have time to post the instructions but I will before the day is over. I have already added/invited 26 people within the last 5 mins.

Live HTTP Header basically was what was used the the script before MW did the check to make sure they are on your friend list. It is great because these invites are not restricted to the MW invite restriction.

Well you install the plugin for firefox called "Live HTTP Headers"

1. Open the plugin and uncheck the box that says capture at the bottom.
2. Get to the page where you invite people from your friends list.
3. Check the capture box.
4. Invite a single friend.
5.There will be a list of stuff that happens, sectioned off with lines. In the 3rd section you want to find the first line which says something like http://apps.facebook.com/mob/do.php or something. It ends in do.php I'm pretty sure, I can't check now because my mob is full so I can't see the invite page on mobwars.
6. highlight that line and click replay.
7. Then in the next window that opens look at the bottom section and you will find the User ID listed. Just change the ID and press replay. Viola. That person will receive a mobwars invite and once they accept will be in your mob.

You can just go to the recently added page and view the source and search for "User_ID" and then just add them useing the header.