The categories for the new search engine on are as follows: speed, accuracy, temporal relevancy, and index size. Here’s how we define those:
Speed: How fast can the new search engine load results?
Accuracy: Which set of results is more accurate to the search term?
Temporal Relevancy: Is one version of search better at capturing breaking news?
Index Size: Is it really more comprehensive than the last version of Google?
Please visit the web developer preview of Google's new infrastructure at http://www2.sandbox.google.com/ and try searches there.