I heard that in cases like that you're supposed to wash the items with vinegar -- if it's mineral deposits from hard water, they'll wash away -- if it's actually etching because the detergent had too much phosphates/water softeners for the water you have, it's permanent.
We live in an area with naturally soft water, so permanent etching has been a staple for everyone here, if you use too much detergent (particularly the ones with a high amount of water softeners [in US that would be phosphates]), it etches the glasses, if you use too little, it doesn't clean. Very annoying.