Actually the Ghost Warriors came out at the same time as what eventually became known as the Wraithlord. Here's the '88 catalog page they appeared in:
War Machines (which shows both Ghost and Spirit warrior robots and the War Walker)
Dreadnaughts (which shows Dreanaughts which were eventually renamed Wraithlords).
If you're talking about the figs listed as Ghost Warriors, you probably will run into static and definitely if you do any tournies. Personally, I would care less, but then I'm captain lackadasical when it comes to that kind of stuff and only care that someone shows up with some cool looking models.
(as an aside, it is pretty sad that
GW is replacing the 18 year old
WL with what, for all intents and purposes, appears to be nothing more than a
CAD-scanned copy of the original sculpt. :\)