How much is too much?

How much promotion is too much? I've heard that the marketing formula to get a buyer's attention is that they must see your promotion a minimum of 7-8 times for them to think about buying your product (book). But lately, I've also heard that potential buyers get tired of seeing too much of the same promo from an author. Have you ever felt that way? Is there an author or company you're sick and tired of hearing about? Or a product? Instead of making you want to buy their product, seeing another commercial or ad makes you want to throw up? Or at least click off and tune them out? At first I thought the Geico gecko was cute. But he was rammed down our throats so much, I got sick of seeing him. I wanted to cancel my Geico coverage. So, how early should we start promoting our new books? And how much? Is it okay to send out a lot of different promos and ads as long as we don't repeat the same thing ad nauseum on several sites or the same loop? Or will repeating the same thing compel people to at least check out our books? You'll also want to see what Amarinda Jones, Anika Hamilton, Anny Cook, Barbara Huffert, Brynn Paulin, Bronwyn Green, Dakota Rebel, Kelly Kirch, Molly Daniels, Sandra Cox, Regina Carlysle, and Cindy Spencer Pape are up to, so make sure to visit them also. :)