That kind of junk should be filtered out, not in, but presumably these nuisance people pay Google money, and hence get included.
Anyway, now a default will be "personalized search" so that based on your click patterns from the past you get a tailored search. Is it a helpful focus or a filtering out of alternatives when you want to look at or for something different, and it keeps routing you to the same old same old?
This page, this screenshot [note the word "enable" because I have already disabled the thing for my web use, and the checkbox toggles between the two options, enable or disable, depending on current preferences]:
NOTE: IT USED TO BE AN OPT-IN TO THE PERSONALIZED SEARCH "FEATURE." NOW IT IS OPT-OUT. IF YOU DO NOT AFFIRMATIVELY OPT OUT PER THAT PAGE LINK ABOVE, YOU'RE IN, WHETHER YOU EVEN KNOW IT OR NOT, YOU'RE IN.
NEVER MIND THE PRIVACY CONSIDERATION. DO YOU WANT YOUR OPTIONS NARROWED BY WHAT YOU'VE DONE IN THE PAST, OR OPEN DESPITE THAT?
THINK IT OVER.
UPDATE - THIS LINK GIVES SOME BACKGROUND [PPC = PAY PER CLICK].
The news is somewhat widespread - here, here, here, here, here, here, here, here, here, here, here, here, here, Google here, and this Bing. That second to last (Google) link and the CNET link before it together seem to suggest that you can disable targeted search by cookie removal when not logged into a Google account but keep it when logged in because your account data is stored server side, not on a client workstation cookie.
The privacy worry, and the pros and cons of personalization are explored in that sampling. I disabled it primarily because I sometimes do searches unlike my prior ones, and don't want to bias the return list in such circumstances; i.e., I often enough want plain vanilla one-size-fits-all non-focused return hits.
FURTHER UPDATE - An interesting series of posts on disabling personal search, especially in Google Chrome where you can disable it by default but have another alternative search choice with it; here (already queued above), here, here and here.
If you read any of that and come away thinking Google is manipulating people, please don't ask me to disagree and talk you out of such thoughts. And if you use more than one browser, or have multiple Google accounts, I make no claim that I have exhausted all you must do, one way or the other, for all situations. Just be aware of the default, and try to get organized as you like it.