The current language discussion on p.g.o is mind-numbingly boring. For the platform libraries we have C, which is easily bindable. For communicating between services we have D-BUS, which is also easily bindable. But to put anything in the platform beyond easily-bindable libraries is just dumb.
Beyond that (e.g. for the desktop), it means that people can write apps in whatever language they like. Even if it's Java. Really, it's ok.