As far as I can work out, it picks out any domain with .edu or .ac.uk and specialist academic web domains, trawls for computer science related content and allows you to open, download and study. Not only that, the Google Code University allows anyone to learn specific content such as MySQL (which is open-source, another good thing) and effective software configuration.
Again Google seem to be spurring on the idea of free content for all, and something I particularly agree with. Education shouldn't hold boundaries; money issues, existing qualifications (to the nth degree, no pun intended) or suchlike. I applaud Google for this - a simple solution by opening up the floodgates and boundaries of different universities, sharing the information for them.
Although this opens up to debate as university students pay tens of thousands of pounds/dollars to study for a minimum of 3 years, yet non-students can search for free content - but ultimately as long as people are learning, surely it's not a bad thing.