Changing which application should open a particular file type

[davewg]

I'll be needing to alter the association either remotely, or via a script or an app, possible 2 or 3 times - so I'm hoping to make the process automatic for a number of users. They could be on Tiger, Leopard or Snow Leopard!

I've been looking into Launch Services, lsregister and along those lines, but not found anything yet. I'm sure there must be a way !