I disagree. A blog can be fetched via RSS and your site not even be noticed. I myself subscribed to a lot of RSS feeds and I wouldn't think in my dreams of buying anything from them, no matter how good they are. And even if the rss only offers a short excerpt of the main post I won't buy a product from there. You have to "take" money from your customers as soon as possible for instance by advertising with AdSense or short-url forwarding monetizers. Hoping that people will like and buy(!) your products because you offer a great game on your page or a great newsletter with information about the niche you are in or a blog is wishful thinking and will not work; it has never worked with me and my efforts regarding this on my own projects haven't worked with other people.
I am surprised that every "how to market on the internet"-guide believes that you had to have a newsletter or blog next to your company to be successful.