Ok, useless weekend. Needed to clean things way, way too much. So finally got rid of the big plasticky green thing with the glowing lights, moved the fish so the cat could torment it in a new place, moved around furniture and vacuumed lots. Nothing fun got done this weekend.
I agree that tag translation should be done as part of the end app, but in my case my marc convertor was just an offshoot written using code from what may someday be the end app, so it was trivial to make it translate the tags. It would be nice if we had a common file format for the tag info... I have a simple format that I load in to do the mappings, but now that xml libraries are more widespread, it should probably be converted. There are just so many fields, subfields, indicators that it's pointless for every project to have to translate them, and most end up never translating them at all.