Twitter is a no follow site that doesn't mean you can't get traffic from it. Get as many followers as you can and then start marketing by posting links and then your followers can share them for you.
it's no-follow as many others have said, but I have found it very useful. I like to promote new blog entries and such, which increases the readership and ultimately some percentage of those twitter followers who read the post will link back to it.
You can make use of twitter only by making many followers to you ,list like face book fans , twitter has followers.