Overhead

When it comes to using a sleek, clean, and easy to parse format, XML is not the only choice. CSV and delimited formats use such minimal formatting, the file sizes are not much larger than the size of the actual data.

Try this. Take a web server log and save it using XML. Using the smallest tag ids possible, there is still a significant increase in size over the base format (some character-delimited format).

These articles discuss GRML (web browsers).

Introducing GRML (web browsers)

Understanding GRML (web browsers)

Introducing GRML (web browsers)