So far, Twitter spam that carries a nasty payload has been easy to recognize. It comes to you as a Direct Message (DM), and it's from one of your followers. But if you notice in the examples below, Twitter spam is generic: It never names you.
Really Nasty Spam - Don't click it. Twitter has not made this software. It's a lie by scum suckers who want to infect your account:
Seven new examples (Thanks, Alice!)
Even more Twitter Spam!
Read about Rob's battle with Twitter spam.
You'd think if it was really one of your friends or followers, that person would be more personal in the DM. But spam can't afford to be personal. It's written generic to try to lure you into clicking the link.
Don't do it. Clicking the link at best takes you to a spammer's site. At worst, it infects your computer with a virus. Somewhere in the middle is infecting your Twitter account. If you've got other examples, feel free to send them my way. I'll add them to this list.
Late breaking Twitter spam
Some Twitter spammers are stupider than others. Have a look at this example.
I ran across these two names, one over the other, in a friend's follower list. You would have thought the spammer would have been smart enough to change pictures.