What about the Google Summer of Code? [1] Google invests millions of dollars every year, both in direct money and in man-hours + infrastructure in random OSS projects. Many of the invested projects are even direct competitors to Google products, most are completely unrelated to Google. But they invest in them anyway and don't make a huge PR deal about it. What about their Solar energy investments? [2] Google Lunar X Prize? [3]

Both are just examples off of the top of my head, of investments that are not directly obvious help to Google. They don't make huge PR fuss about them. (Which I suppose is why you didn't hear about them) But instead they are indirect longer term benefits to Google, in the same way that fighting for gay rights is. So this is certainly not a first time thing. They've been doing this kind of thing for years. Unfortunately you cannot help everything in the world at the same time. So you cannot rule out what they done before just because they're not helping solve specific problems.

[1] http://code.google.com/soc/

[2] http://latimesblogs.latimes.com/technology/2011/12/google-in...

[3] http://www.googlelunarxprize.org/