I know I wasn't, but at least I tried, aye? ;)
About the API, I'm guessing that it'll focus on feeding Google News, including News results in Google Web Search, but not GWS itself. I'm also guessing that many a publisher will be too lazy to make the 5 articles a day properly and instead just stick to the behaviour where coming from or being Google gets you the full text for free, but anything else (including clicking any of the internal links you see on that free page) would go behind a paywall. Should my guess prove true, the methods as described above will get you free full articles.
And for those papers who actually implement a five-a-day-free, it'll either be done with cookies (flush 'em for another five free stories), your IP address (reset your router, use TOR, use CoralCDN (.nyud.net), use a proxy) or tied to your Google Account (very unlikely, but solvable with more Google Accounts.)