I'm in charge of both sales and marketing at Websystems. This is highly irregular: at most companies, sales and marketing are kept separate.

However, in a small company like us, it makes more sense to have one person do both sales and marketing. Since our business is online, I can do live demos and write a press release in the same day. I like to keep contact with our potential customers, because it keeps me connected to what people are looking for in a project management system.

It's very important for marketers to know what their audience is looking for. And it's very important for the sales team to understand well how marketing wants to present the product. 

At Websystems, having both sales and marketing in the same person is beneficial. I get good contact with the market, and I can align my campaigns with current and upcoming trends.