Not a virus though, a worm...
People are able to use it to XSS attack1, basically post some javascript on twitter.com2 that will be executed. Mostly this javascript is then making you post another tweet without realising it, passing on the original code. This is a neat twitter worm, not actually a virus. Some of the javascript may redirect you to sites that do try to infect your computer. Look out!
js: Programming language of the web, mostly how I earn a wage.
Paul Clarke's weblog - I live in A small town. Married to Clare + dad to 2, I'm a full stack web developr, + I do mostly js / Node, some ruby, python, php ect ect. I like pubbing, parkrun, restaurants, home-automation + other diy stuff, history, genealogy, Television, squirrels, pirates, lego, and TIME TRAVEL.