Implementing large scale web analytics

Does anyone know of any articles or papers that discuss the nuts and bolts of how web analytics is implemented at organizations with large volumes of web traffic and a critcal business need to analyze that data - e.g. places like, eBay, and Google?

Just as a fun project I'm planning to build my own web log analysis app that can effectively index and query large volumes of web log data (i.e. TB range). But first I'd like to learn more about how it's done in the organizations whose lifeblood depends on this stuff. Even just a high level architectural overview of their approaches would be nice to have.