At SMX East yesterday, during the Trends in Mobile Search session, Google announced the addition of cross-device conversion reporting in AdWords and I believe this may be related to the loss of referral keyword data in Google Analytics. The new method of ad attribution helps advertisers understand cross-device and cross browser conversions, and eventually will also include attribution for click-to-call and offline conversions—a panopticon of conversion tracking! It is great for advertisers, but I believe it may have pushed mobile privacy concerns far enough to cause Google to pull back the keyword data in Google Analytics (and may possibly have caused the recent hiccup in Google Webmaster Tools as well).