Part of my distaste is because I miss the dedicated search button on newer phones (and long press for voice search), but in any case I just don't see the point of Google Now.
1) It's awful at answering questions. I've asked questions in plain english maybe a couple dozen times and almost every time the result has been a simple web search. Not a "card" with an answer on it, which, as far as I can gather, is the point. The only times I've gotten the card were for questions I was only asking to see what it CAN do, since it CAN'T do anything that seems to be useful.
2) The simple answers it can provide are much easier to find in a dedicated app. If I want to know the weather, I look at a widget or open a weather app. If I want to know what's on my agenda, I look at a widget or open the calendar app. I'm not going to open Google Now and see if it happens to have a card for the specific information I want. And the general things it does are all important enough that I have widgets for them that I can see at a glance without opening Google Now.
The only thing it's been able to "do" other than this is simple definitions of words, which I suppose is a little easier than doing a web search, but kind of "meh."
The swiping up from home button thing doesn't seem like it should be THE way to see what Google Now wants to tell you. The passive nature means none of it is immediately pertinent information, yet you have to take action to see it. A widget would make a LOT more sense. As it is, I don't ever find myself thinking "I wonder if there's any random, currently unimportant information I'd like to see." And I'm very rarely in a situation where I don't feel completely ridiculous talking to my phone.
Who uses this thing? Why?