There is one main reason people in the open source community get so violent over Mono (the open source .NET implementation): the fear that Microsoft could shut everything.  There is long standing fear that MS has patents on core parts of the system.  People were afraid their investments in software written on top of it would be at risk.  Java was always held up as the much safer choice, with a longer legacy, being more open source friendly, with a company behind it that everyone trusted.  Of course, companies change hands some times….

Oracle sues Google for patent, copyright infringement

Oracle filed a complaint in federal court in California, alleging the infringement of seven patents and copyrights by Google’s Android mobile operating system software.

I was once told that Sun actually made money off Java, and one of the big sources of revenue was the J2ME market, which is what all those dumb little snake games are written in.  Google has undercut that by making a really popular cell phone platform with a version of Java they wrote themselves.

It’s still not a good world to be in, where innovation comes with a 10% patent tax.