As pinkunicorn says, there will be a green 'tick' for ones which have corrected co-ordinates. The thing is with that though, that you have to actually correct the co-ordinates on the cache page first, before project-GC will recognise it.
To do this, go to the cache page and click the pencil icon next to the co-ordinates. It'll then ask you to input the correct co-ordinates. Once you do this, Project-GC should pick them up the next time it runs your stats (or at a similar time) and it will show on the PGC map.