Ok, I'm starting this as the official porting tip thread - if you come across something that everyone else should know, put it here!

If you've found success in porting your software, let us know how you did it! What challenges you faced, etc. This will help everyone out - sharing your knowledge will equate to you and the rest of us getting all the great OS X apps we love a little quicker.

So share what you've learned! Write a guide or an FAQ, or simply give us some pointers! Your efforts will help the entire Mac community!