(Update: 15-10-2012) First read this
You don't like/understand the svn diff output?
You would prefer a better tool with merge options and appropriate coloring?
Kompare is a great tool used by kdevelop to compare files. You can find it in the repositories of all famous linux distros or here
But how could you use it as svn diff command?
I 've written a ruby script based on the script svnvimdiff, written by Geoff Buchan that will let you svn diff your files with kompare.
Click here to see and get the script.
A usage example is the following (diffs/compares "file" with the last checked in "file")
svnkomp.rb -f file -- -rHEAD