I wouldn't dismiss plain text, like CSV or tab-delimited.
I'm really looking for alternatives that have a defined structure and (cross platform, multi language) library support. I'm interested in looking at different designs and their pros and cons. I like the idea of formats that can have a text and "binary" (compact, "compiled", fast I/O, smaller footprint) format. The advantage of having libraries is that they perform the parsing and perhaps extra data manipulation/validation for you.
Although having said that, there is definitely a use for simple formats like .ini, .plist and CSV etc. You shouldn't always have to use a hammer to crack a nut.
