Google is now considering page layout as part of their ranking criteria. Although they claim actual search results affected will be under 1% we know every time Google makes an estimate like that you should add 10 points to the number. It'll also be interesting to see if Google will penalize their own search results (no) due to too many ads in the header (some search results pages are have entire page folds notoriously littered with ads).
Nonetheless, webmasters should pay attention to what's already evident.
Ensure you build websites for users that are beautiful and practical. Come to think of it, this shouldn't be news or even an issue for innovative designers and marketers. After all, stuffing the top page fold full of ads is not only looks cheap, it's an act of desperation that rarely pays off in spades (the money spades).