Luis Mazza, on 20 November 2012 - 13:09, said:
I think it may be useful if you're on a routine with your life, otherwise I don't like the battery to be constantly drained. I like to go for the maps app and check traffic, destination and weather when I want to, not when the phone thinks I want to.
Voice search is neat, though.

After the introduction of Google Now, I haven't noticed any significant battery drain...It's a smartphone, I'd rather it have me tell all these things, otherwise what's the point of owning a smartphone?. If you don't want it, you can always opt out.