Came across this 3-part long article which gives a comprehensive
insight on the development/testing/deployment strategies Microsoft
used for their Windows 2003 operating system. Though a very long
article, it is worth a read for everyone. Gives an idea how difficult
it is to develop and deploy a successful software product.
To quote Mark Lucovsky (Windows Server Architect) from this article:
"There are 5000 developers on the Windows team generating over 50
million lines of code for Windows Server 2003. It's an enormous task,
the biggest software engineering task ever attempted. There are no
other software projects like this."