To what extent can third party Android apps access the apps in the market? Can they grab titles, descriptions, and categories for all of the apps there? Can a third party app download an app from the market (or at least download free apps)? Can a third party app update another app?

I will choose a winning answer within one week (unless nobody is able to fully answer it). Winner will be chosen based on completeness of answer (if you can cite your sources, that's a big leg up). I'll contact the winner for your paypal address, and yes, you're just going to have to trust me.

EDIT: Sorry mods, this might be the wrong category? Perhaps this could be moved to Jobs?

Found enough of an answer to my own question:
http://strazzere.com/blog/?p=293

Reward offer withdrawn. Seriously, no takers?