If you just want to figure out, what files
will be updated and exactly what will be changed you might use this command.
svn diff -r BASE:HEAD .
This will display the differences between current files in the directory (BASE) and the latest revision at the repository (indicated by HEAD).
Just for the record, here are some other useful hints.
If you just want to have all updated files:
svn st -u
This however does not display all conflicted files, so you might use
svn merge --dry-run -r BASE:HEAD .
