Isn't that exactly what MS AdCenter is aimed at (removing Googles oxygen supply I believe). Google responds by creating a better product rather than fixating on killing a rival.
Well Apple and Google seem to be in the business of making good products before profit (they do make profits but only because they make good products).
They both provide products with less features on paper than MS rivals but the quality and attention to detail on Google and Apple products are light years ahead.
Microsoft just aims to make their product look similar to middle management so they buy it over the competition. VMWare is a good example here. They make an excellent product that does things you can barely get your head around, but MS decides to release their very poor virtulization product and claim it is the same to try to kill any competition. They do not have the customers interests at heart when making products.
Apple has agreed now to work with KHTML people and give back changes to webkit. They may have upset a few people but they have put making up with those people over their profits. Did Microsoft ever give anything back to the BSD networking stack?