One of the first main challenges for a company that has been acquired by Google is adopting the proprietary technology stack used within the company. Google does use Linux and open source, but their core technologies are all internal to the company. I have heard that it can take a new engineer at Google anywhere from 3-6 months to become accustomed to using these tools and services. The table below sets out the Google stack and the technologies used:
Google Technology Stack
C++, Java and Python Core libraries and components in C++, web applications in Java (Google Web Toolkit) or Python (not as common)
MapReduce Distributed computing library and cluster. Written in C++ can interface in Java or Python
Big Table Distributed column-oriented data store with query language.
Google FS Large-scale distributed file system. Used for object/file storage
Because of the difference in technology, it can take a company anywhere from a year to three or more years to move over to the Google infrastructure and architecture. Blogger was still running their own infrastructure until their new release last year, and they have finally integrated Google ID’s. YouTube is one of the only recent acquisitions where full steam and emphasis were placed into getting the site moved over to run on the Google platform. YouTube managed to pull it off, but it is a rare case inside Google (and also a special case).