The central reason that Twitter is hard to spam is that it's all based on followers. Marketers who have tried to use Twitter to blast their marketing message have found it difficult, because no one is likely to follow them. So, there have been a bunch of methods spammers have used to trick users into following them, the most common being the use of a photo of an attractive woman for their image (when it's likely some fat guy who's actually behind the account).
The newest approach is to try to assume the identity of another popular Twitter user. In the past few days, I've received a bunch of follows from users whose names appear to be the same as someone I follow, except they've added an underscore at the end of the name. So, instead of Barry Schwartz' @rustybrick, it's some spammer using @rustybrick_ as the ID. They even go so far as to steal the image that the original user has for their ID.
Luckily, the spammers seem to be getting caught pretty quickly. By the time I've tried to click through to their profile pages, I see the Twitter Suspended account message.
I've no doubt that the spammers will continue to explore creative ways to try to gain followers, particularly as more newbies join Twitter. Having brought a number of new users to Twitter myself, I always caution them to use the following approach before following anyone back:
1. Check the website link and bio
2. Look at the number of tweets they've authored. If it's just a handful, there's no reason to follow
3. Look at the following:followers ratio. If it's more than 3:1, it's a warning sign
In the meantime, I'm sure the team at Twitter will continue to tweak their algorithms to detect spammers.
