SEO delivers the right message at the right time to your customer base. If you send this traffic to an inappropriate – not conversion focussed page – you’ll see conversion being weak. Your visitors can hit the back button – why should they make another click in the hope that you’ll fulfil the desires you said you’d satiate by clicking on your website to get to the place they need to get to.

Your homepage is a segmentation page – its job is to get prospective customers to the information they need quickly. Its going to be hit with brand traffic – that you have no idea of what they’re looking. That above the line campaign you’ve been running has delivered new interested visitors but you dont know what they want as there is no intent within the keyword.

You know through generic keywords, and the longer tail that falls from these, that people have an interest in a product, group of products, so why send them to a generic page. With mixed messaging and multiple offers. Get them to the page most appropriate.

More at http://www.imjuk.com/2009/07/why-seo-is-not-about-positions/