There seems to be a broad split of opinion here between those who have operated large scale UAVs (Pred/Reaper) and those who haven't. In terms of current usage, such as ground attack through a targeting pod, there really is no need to be physically 'there' - and trust me, as one of those who 'has', you are very much mentally 'there'. Air-Air is probably a totally different ball game, but as I have no experience in that arena I can't comment.
Your battlefield SA from operating a UAV is usually far superior to that of a manned aircraft, particularly FJ types that are endurance-limited. By the time you get into a fight, you have probably already 'been there' for several hours and built up a very broad picture of the battlespace. It is often you who is briefing-in the FJs that rock up much later on in the party. And as already mentioned, the range of SA tools available to a UAV crew is vast.
I echo the comments from the likes of FFP, Mr Grim, Bear 555 and L J R here. They reflect the reality of my own experience. UAVs are most definitely not a panacea, and will only ever complement, not replace, manned aviation.