People ask me this often enough that I figure I should write it down for easy reference. Here is my position on the “tabs vs. spaces” technical debate:
1. Use whatever style is in use already in the project.
2. If it’s a new project, pick whatever you like.
3. The productivity gains of any particular style over the others are totally, vastly outweighed by the productivity hit of constantly arguing about it.
In summary: I don’t care which you use as long as I don’t have to talk about it ever again.