The green washing aspects would be carbon offsets and such because those are still up for debate as to whether they really have any positive net effect.
Edit: Got a downvote so I thought I'd clarify. Carbon offsets are the act of paying for carbon neutrality. No matter how efficient or environmentally friendly Google is, they can't possibly be carbon neutral with all their energy use unless they use primarily nuclear power with some hydro, solar and wind built in. Therefore they buy carbon offsets, http://en.wikipedia.org/wiki/Carbon_offset, which allow them to advertise that they're carbon neutral. The controversy over them stems from the fact that they're very similar to indulgences from the catholic church in the time of Martin Luther; paying for greenness isn't actually being green.