To quote Martelli from Google talking about how the Youtube startup outran Google Video's might so much that they had to buy them:
"Eventually we bought that little start up and we found how 20 developers ran circles around our hundreds of great developers. The solution was simple! Those 20 guys were using Python. We were using C++. So, that was YouTube and still is." [1]
Google took months to copy new YouTube features, while YouTube could catch up in a week after Google innovated.
[1] Google Books, search term 'python interviews google vs youtube'