Why not make it completely customizable?
Hard coding things like this is never going to appeal to all users (eg: Lukas' comment).
For each item added to the list add a checkmark which indicates how the replacement is done. Eg: only at end of sentence, words only, all characters, etc... Or make it accept regular expressions so the user can do whatever he wants...
EDIT:
quote:
Originally posted by vikke
Thank you for your suggestion, next release! 
whoohooooo!
/ 
