From an old business classic, Loyalty Effect, Frederick Reichheld's approach to employee loyalty is refreshing: sniping high quality talent from other firms is unfair to loyal employees and sends the wrong message: that the best way to make money is to hop firms. Google and Facebook are setting a precedent that will lead to short sighted hiring cycles and unneeded office drama.
So my buddy Nathan was learning how to code PHP about 6 months ago. His first project was just a one off / fun web app called http://www.Natebook.com. Anyway, he knew the site would never catch on or be viable, etc. because facebook could just send him some cease and desist letters and shut it down.