Google Now Questions.

Hi All!

I'll be buying a GNex in a couple weeks but had a question I couldn't find an answer too anywhere. The most attractive thing for me about android project butter (looks amazingly smooth...) and Google Now (As someone who actually find Siri useful, I think Google just took it to the next level....). Now, based on everything I've read/seen, it seems that Google Now is limited in so far as customization (I understand the individual cards have settings, but there is now a general setting on google now itself, except weather or not to use it.) I seem to remember someone (Josh, maybe? or Chris?) saying you can't even program where you live, it just picks it up overtime. Well I work graveyard shift. My issue is, is google now going to flip my work and my home, thinking that the time I'm at work, I'm actually "sleeping?" and when I come home, I'm at work? Or is there a way to confirm or set what it attempts to learn? Any feedback would be greatly appreciated from anyone who may already be using it! Is it cool? I'm really excited!

Thanks guys!