Google announced today that a new keyword analysis page inside Adwords offers more insight into why Google scores ones keywords with a certain quality score. I hope this actually works. Optimizing of campaigns was very difficult sometimes since Google Adwords introduced the Quality Score.
 
Quality Score influences your ads' position on Google and the Google Network. It also partly determines your keywords' minimum bids. In general, the higher your Quality Score, the better your ad position and the lower your minimum bids.

Quality Score helps ensure that only the most relevant ads appear to users on Google and the Google Network. The AdWords system works best for everybody—advertisers, users, publishers, and Google too—when the ads we display match our users' needs as closely as possible. Relevant ads tend to earn more clicks, appear in a higher position, and bring you the most success. If you want to know about Google`s Quality Score, you can go to this site on Google.com.

On Searchenineland they have a little bit more insight about the latest changes:"Now, if you have a poor quality score, Google may share a reason. The reason can be found by viewing your keywords tab, then clicking on the magnifying glass icon beside any keyword, and then clicking on the "Details and recommendations" link. On that page, you can find out if your quality score is low due to your landing page, due to your ad copy, due to the relevancy of your keywords to your pages, and other reasons."