I'm afraid you haven't really used voice commands on Android. They do lack the NLP of Siri and the witty responses, but in practice they seem much more accurate at actually understanding what the user is trying to do.
Also you may believe iPhone is king in the ease of use department, but I don't. I think after using either OS for an extended period of time they become second nature and usage of the other can be grating if expected behavior is different. Personally I find Android much easier to use, you may not, and that's okay.
From the Wall Street Journal: "However, I found the iPhone 4S worked better than the Galaxy Nexus in noisier environments. For instance, in a crowded shopping-mall food court, while neither phone was perfect, the iPhone understood me to say: "I am dictating this email from the very noisy Court at Montgomery Mall on the iPhone"—missing only the word "food" and capitalizing "Court." The Android phone mangled a very similar sentence as: "I am dictating this email on droid phone from the bearing noise for it montgomery mall."
Detailed review by owner of both: "Siri is handy for sending quick messages and looking up basic information, but Dictation is the real winner in my book. I use dictation on the iPhone 4S to write entire articles with enough accuracy that only minimal editing is needed."
Also you may believe iPhone is king in the ease of use department, but I don't. I think after using either OS for an extended period of time they become second nature and usage of the other can be grating if expected behavior is different. Personally I find Android much easier to use, you may not, and that's okay.