So what are the killer apps? How about things like Launcher Pro, Swype, SwiftKey, and AppBrain? Why don't we talk about Chrome To Phone or the FM Radio listener (via Cyanogen)? Those are all things that just don't - and can't - exist on the iPhone, but the glory of them is that I get to choose them. I can pick my own homescreen app and tweak the heck out of it. I can pick an input method that I want (SwiftKey has made my iPhone-using friends turn green with envy on more than occassion). I can install new apps without ever having to tether to my computer with iTunes. I can send a map or recipe from my computer to my phone and take my work with me seamlessly. These are all "killer features", but they aren't "apps" in the Apple sense of the word - they're features, extensions of the platform, which let me use my device as best I see fit.
If everything Apple does is exactly what you want, Android probably doesn't have any "killer features" worth talking about, but as soon as you want to do something that diverges from the Cupertino Grand Unified Vision, Android starts to become a lot more attractive. Given Gruber's leanings, it's little wonder that he's not enamored with Android. Doesn't mean that's the case for everyone - and the market bears that out quite well.