Aww look! I got a troll! So cute. =D
The app store on the G1 is smaller, but I've found everything I need to actually use my phone, rather than just eye candy. The stability has been top notch, and I know this is regionally based, but the signal quality for me blows AT&T away.
I could jailbreak the G1 but I haven't found a need yet. I haven't tested yet, but from my understanding the app store works just fine on rooted phones. Oh and I can upgrade the storage or battery, or carry multiple batteries if I really wanted.
Don't get me wrong, I like the iPhone, but the G1 fits my needs. I just don't have a use for 9980 "Wooo" buttons.