Just a quick note to mention that earlier today we added the ability to search within citing articles to Google Scholar. This has been a popular feature request :) It allows you to search the complete text of the set of articles/cases citing a document, It can also be used to limit the results to citations from specific jurisdictions (via the dropdown on search pages or the advanced search page).It's a pretty simple addition, but one that may assist researchers in narrowing the amount of information they need to search in order to find what they are looking for. Here's a snapshot of the new feature:
A blog post describing this with examples and an illustration is at the Google Scholar Blog
It seems that the handful of folks at Google Scholar are still listening to their users. So, if you have any further suggestions, you should contact them through their suggestions page.