The main difference is that Catorize, as its name implies, automatically categorizes apps using information that is already in the packages. You can override that if you wish, but overall it works well. This is way better that MyMenu, which does the same thing but with the poor author manually adding apps to categories as they appear. My guess is he'll get tired pretty quickly...

Credit goes to the MyMenu author for having the original idea and first implementation. Right from the start Jaffa pointed out the right way to do things, after a while he got tired of waiting and did it himself, hence Catorise.