Stephen O'Grady has some good insight on the Google-Sun partnership, Google/Sun: Overhyped or Undervalued?. He says two things that I really like. First,
So if one assumes that the participation in the JCP and the rumored hiring activity is done with a clear goal in mind, the question is what goal is that? From the Java side, I think the benefit to Google would be clear: just about every client side application they've developed to date has been Microsoft specific. The Google Toolbar was originally IE only, and both the Google Desktop and Google Talk are Windows only. This is in stark contrast to their thin-client offerings, which in general could care less what operating system you run on. Might Java be a bridge for those applications to other platforms? Could be.
Second,
The other interesting aspect of the deal that no one's talked about yet that I can see is one that's a bit outside my coverage: the hardware. After today, I'm really curious as to whether or not Google - the datacenter to end all datacenters - is looking into Sun for power reasons.