I have found the exact opposite of the comments in this article to be true. Case in point. The company I work for recently decided that Marketing was important enough to actually spend long over due money on their marketing strategy. At first I was glad of this. Over my objections the site for the company now is a Flash nightmare.
Usability is a very important area of engineering.
I agree that each person has their job on the team however saying that the Marketing team members should control the over all structure of the site is dead wrong. The look and feel of the site is a group effort. The team lead has to be a little of everything and balance out the equation. Hold the designer in check, let the engineer do his job, and make sure the message gets out and is not lost or overwhelmed.