In our first year of Computer Science (High School) we wrote a few games as end of year projects using XMLs to store information and save info.

We loved the flexibility and structure XMLs gave us but ran into problems in maintenance the next year after Java had released 1.5.0 and rewrote it's XML handling functions.

I would tell you to go with XMLs but keep in mind that the way your language handles XMLs can change, the way it handles text won't.