Google has always truncated the display URLs in the search results when it went beyond two lines, I believe. But now new reports from several sources are noticing that Google may be truncating the URLs to a single line, when applicable.
Below is a screen shot of Google shortening URLs. As you can see, the eBay URL goes two lines but every other URL I found that went two lines, Google seems to be cutting down to one line. And Google seems to be cutting them down, while keeping the keywords in the URL.
Related Topics: Google: SEO | Google: User Interface | Google: Web Search
Wow, I just began seeing this today and wondered if it was something happening all along that I had missed. Find myself mousing over the snippet title tag to see full urls before clicking through. :)