Trying various searches was an interesting exercise. Google's suggested use, comparing hybrid cars is a pretty good one of Google Squared's potential as it finds a wide variety of cars and allows you tweak the search nicely, easily finding prices, fuel economy (MPG) ratings, and hybrid models that don't appear on the grid at first. Searching for a less environmentally correct type of car yields decent but clearly inferior results. (At one point, Google Squared actually displayed an MPG rating of 100 MPG for a Hummer H3 thanks to this blog post. A pop up list of possible alternative values which were labeled as "low conficence" lead to this Wikipedia page which displays fuel economy ratings for American cars which I would have thought would be regarded as fairly accurate considering how heavily Google Squared relies on Wikipedia for its information.) Similarly, a search for Atom powered netbooks yields decent results but has trouble finding prices for them.
I thought that Google Squared might be good for comparing politicians based on their stances on issues but that didn't work out quite so well. Searching for "Illinois congressmen," Google accurately found and displayed information about current and former Illinois congress people. But trying to add information on their stances on an issue such as a abortion or immigration yielded no information. Similarly searching for a specific piece of legislation like the Employee Free Choice Act yielded no information. Searching by that bill's ID number (H.R. 1409) in the House database also yielded no results even though putting that number into Google normal search box finds it immediately. Curiously, inputting the word "liberal" does yield rankings for some of them based on a Wikipedia article on RINOs (Republicans who are considered "Republican in name only" because they not conservative enough for the party "base").
For all its flaws, Google Squared shows great potential as a comparison tool. It's no alternative to Wolfram Alpha (which is still in its infancy and defies easy categorization). But Lifehacker also compared it to a spreadsheet and on this they are spot on. Google Squared is just begging to be integrated into Google Docs and might even be better off being absorbed into them as an analysis tool.