The most important thing is content. Personally, I would say the more people you can get to write for it, the better. Articles and commentary are both great, but make sure they are original! People may find your blog, but if you don't update regularly AND have interesting content they won't be back. Build up a base of loyal readers to really see the traffic jump up.
Submitting on sites such as delicious and digg will also help, but again, to get to the top of these sites your blog has to appeal to readers.