Technically NDBs are required for offshore approaches to platforms although there is no practical reason why we couldn't use GPS. Offshore we more or less have to have GPS and it is great. But we have either an on shore NDB or the appropriate rig NDB tuned at all times. It is always nice to have a spare needle pointing to where you want to go. Given we only have one GPS and often no radar or VOR coverage, the NDB is the only back up we have.
I am sure the days of the NDB are numbered, but it seems a shame to loose something which is so simple to use. Yes it is not terribly accurate and has some gottchas, but it will get you to a position where more sophisticated nav aids will get you in. Having said that the trial GPS approach for Durham Tees Valley had higher minima than the NDB approach did. Let's hope that when we finally get widespread GPS approaches the minima are at not worse than the anitque it replaces. Otherwise we'll only have backward progress.