I knew the day will come when some smart aleck will do something like that. I believe more will be up to trick people into providing their passwords or even sensitive stuff through twitter.
Recently, there has been scam page that looks like Twitter login page. So, be careful when you get a direct link with Twitter on it. Remember to look at the actual URL. It should only be http://Twitter.com.
These phishing websites are abundant on the Internet. However, it is my first time to see it on a social network (although I remembered that there was a case for facebook).