For building Google's search engine, you need people who know search and sorting algorithms backwards, forwards, inside-out, and upside down. You need hardcore A/B testing based on statistical significance, and rigorous respect of the data you collect.
To make the iPhone and the iPad, you need neither of those.
You need one guy who will walk around like an idiot for months pretending that a deck of cards is his telephone, and writing down every observation and thought that he has on usability. You need a master craftsman who can direct the entire experience, without losing his head in the tech specs.
Google doesn't hire people like that. Decisions are made by committee, backed by data and research, which gives them their edge in technical excellence, but also cripples them in hardware and marketing.
It kills me. I really want Google to succeed here; Apple has effectively zero competition in the smartphone and tablet market other than Google.
Ok, what follows is a bit of a rant. :)
Personally, the first thing I'd do with Android is revamp the market and distribution model to standardize the OS across platforms and vendors, so that an Android works the same no matter where you got it. Vendors can add in custom content (wallpapers, extra apps, ringtones, etc), but the interface (icons, look-and-feel) needs to be the same.
The vendors will go with this. They're getting their asses handed to them by Apple, and Google is their lifeline, because they're saving a ton on development costs.
Second, I'd market the hell out of the areas that Apple cant match, but that matter to the consumer, namely voice search, and maybe being able to hold the phone in the human hand without losing reception.
And whatever you do, don't play the celebrity card. Apple's iPhone and iPad ads make it look like you're using the device. Google could steal a page from that, but with Android devices being used in the real world, not in the Apple cleanroom.