Sounds great Rafael. I've been thinking about this sort of thing since writing the first OS X install doc. I would like to take part in the work.
Here's a follow up to my earlier post about the person who said that they had some Applescript developers working on this. I was unable to find the specific email. So if the person is reading this, it would be great if you could step forward.
On another note, Mark Darymple has a doc or a draft of a doc on Apple's Package Manager that might be helpful and he said he could make it available.
