According to Rahul Kashyap we'll be hearing a lot more about malvertising. See http://www.wired.com/2014/11/malvertising-is-cybercriminals-latest-sweet-spot/
Third-party ads are "quietly displaying on these pages and sometimes burrowing into viewers' browsers and PCs before they even click anything," is how he describes it.   His short article in Bottom Line/Personal declares that malvertising has already invaded extremely popular sites including Amazon, Answers.com, Yahoo and YouTube.
  Malvertising relies on a trusted destination to bring in a target for their attack. Site operators often have no knowledge of malware on their own domain. Cybercrime rings are brutally efficient and do not bother with unnecessary effort, cost and exposure.

Rahul Kashyap is Chief Security Architect and Head of Research at Bromium. Part 2 of this series is already online. Find info at bromium.com and be aware of the growing problem and what you can do to protect yourself.