pops117: I'm just so put off by Microsoft's close-mindedness in regard to what you may install or not, anything not from them is banished or copied in some inferior way...
Windows Operating System for PC I can customize to some extent and install the stuff I want.
Rereading myself I actually see how this could also apply to Apple (not as bad though), Google is not as restrictive on the other hand they're not as 'open' as they pretend to be.
Can't talk about the homebrew part (if you were refering to that), as I don't own iPhone or an Android device to have homebrew tested on them, but for marketplace apps, restrictions are a must.
Just look at Android's marketplace the last few months. Many apps are actually malware!
Also, Microsoft will be introducing new APIs and will open the platform more with the Mango update, that's why I mentioned it previously, in there might be something you like.
Oh, and the whole update "horror" stories... they have nothing to do with Microsoft actually, it is Samsung the bad guy here. Two phones, Omnia and Focus... with a dozen different firmwares for no good reason, and what else not. :) Other manufacturers have been error free.
EDIT: Sorry if I sound like a Microsoft fanboy, I'm just happy with my WP device. :p