Achievements are nice, however I'd like to see Bethesda (along with all the other game companies out there) assign some real-world value to them, aside from bragging rights.
Discount on merchandise for example, for every 50 trophies you have from playing their games. T-shirts, pens, hats, posters, etc. Since Bethesda has a string of franchise hits, I think it is something which could be plausible if done right.