Google now made it easier to know when you're affected by a landing page or site policy problem, rather than a landing page quality problem.
What's changing in the AdWords interface?
"Previously, if a destination URL wasn't compliant with our landing page and site policy guidelines, the associated keywords would show a Quality Score of 1/10, a notice that ads were rarely showing, and an indication of poor landing page quality.
However, you wouldn't see anything explicitly mentioning a landing page policy violation. Now, if your keywords are affected by a landing page policy issue, here's what you'll see on the Keywords tab in the AdWords interface," explains Google.
"Affected keywords will show "Site suspended" in the status column. And since affected keywords aren't able to trigger ads, a Quality Score is no longer calculated or shown. If you switch to the Ads tab, any ads that aren't serving as a result of the policy violation will show a status of "Suspended."
These changes are visible for most landing page policy violations. For serious offenses, however, remember that we may immediately suspend an account."
[Source: Google Inside AdWords blog]