Does anyone know or have information about which Software Development Life Cycle methodologies are used by Google?
Steve Yegge wrote a long blog post that discussed life at Google including their development methodology:
He notes that
From a high level, Google's process probably does look like chaos to someone from a more traditional software development company
He goes on to describe working practices, product launches and Google's incentive programs. He concludes with:
I've outlined, at a very high level, one company's approach to software development that is neither an Agile Methodology, nor a Waterfall cycle, nor yet Cowboy Programming. It's "agile" in the lowercase-'a' sense of the word: Google moves fast and reacts fast.