I need this to be fixed too.
It is my single MOST HATED thing on OSX, and has been for years.
I hate hate hate the stupid lack of basic functionality in the copy dialog box.
I am not the only one.
Many forums such as this one have tons of pages about how much they hate this issue.
http://forums.macrumors.com/showthread.php?t=274241
There are people in that forum who switched back to windows because of just this issue, and as much as I love osx, anytime I have to do file management, I consider switching to a windows pc as well,
because finder makes file management a nightmare on the mac.
Windows has it exactly right in this regard.
It gives you many options in merging / skipping / replacing / aborting;
in merging, the many options are things like :
To select the action to take on a per-file basis for every file within a folder and all it's subfolders,
or
to perform the same action that you choose [replace? keep both files, renaming one of them? Skip?]
for one file at a time, or to apply that same action to the whole folder, or even to all the files in all it's subfolders.
In this regard, Finder is just the worst. I hate it.
File management tasks that take me an hour on windows can take literally DAYS on a mac.
Just ridiculous.
Please fix this DINOSAUR of an application. It is stuck in the 80's.