"Follower services" to stay clear of

You will occasionally see tweets recommending services that promise a lot of followers by joining and then following the users that are listed on that site. This may seem like a good idea at first, but please consider the following caveats.

• First of all, you are giving the service your twitter username and password and are giving them permission to send advertisement tweets as long as you are member of the service
• To comply to the rules of the respective site, you have to follow everbody which will leave you with a lot of "marketing" accounts that probably want to spam you even further
• You will probably follow considerably more users than you receive followers, regardless of what the site claims
• The followers you get are not topical interested in you, they are just following you due to fact that they joined the same site
• If you want to buy the "VIP" membership of such a site, keep in mind that the services may be rather short-lived and you probably not get any refund when the site goes down (see sample list below)

In all, I would suggest not joining any of the sites, if you already have joined, cancel your membership and change your password (if you cannot cancel your membership, just change the password and complain to Twitter.com about the abuse).
Sites operating with the same concept include the following (some of these sites are exact copies of each other with exchanged service names):

• http://www.iwantfollowers.com/
• http://www.morefollowers.info/
• http://www.extrafollowers.com/
• http://www.addfollowers.info/
• http://vipfollowers.com/
• http://www.tweeterfollow.com/
• http://NeedFollowers.com/
• http://www.youradder.com/
• http://mytweetfollowers.com/
• http://followadd.net/
• http://tweeterattack.com/
• http://www.twittershuffle.com/
• http://followersfree.com/
• http://followersnow.com/
• http://ineedfollowers.com/
• http://thousandfollowers.com/
• http://followersfast.com/
• http://the-twitter-follow-train.info/
• http://www.followersplus.com/
• http://bestfollowers.com/
• http://findfollowers.info/
• http://twitter-follow.de/
• http://follow-u-follow.me/
• http://twitterfollowtrain.com/
• http://www.twitter-follow-train.info/
• http://hugefollowing.com/ 

Feel free to visit any of the sites, I just wouldn't suggest them.

There are also quite a few more domains that forward to one of the services via an affiliate link, so if you end up at a domain from the list above with an added referral id, the same caveat applies, obviously.
E.g.

• http://www.getfreefollowers.com/
• http://www.moretwitterfollowers.tw/

The reason behind this is obvious, the services want to avoid becoming blacklisted.
(Updated 07/25/09)