An anonymous reader writes "A report released this morning looks at the maintainability level of the Firefox codebase through five measures of architectural complexity. It finds that 11% of files in Firefox are highly interconnected, a value that went up significantly following version 3.0 and that making a change to a randomly selected file can, on average, directly impact eight files and indirectly impact over 1,400 files. All the data is made available and the report comes with an interactive Web-based exploratory tool." The complexity exploration tool is pretty neat.