If you've ever attended a Microsoft conference/event, you'll know that they have a pretty good sense of humor, often demonstrated in video form.
This was no different from the Microsoft Global Exchange conference, held only last week. The video is meant to parody how Google's Gmail "rifles through your email", a not so subtle remark on Google's advertising business which shows targeted ads in your browser based on "keywords" in your email.
For those concerned with privacy, Google's whole ecosystem is ripe for criticism. If anything, this video should get folks talking a bit about such matters. At the very least, it's pretty freakin' funny.
Source: All About Microsoft/ZDNet