When I first entered heaven I thought everyone saw what I saw. That in everyone's heaven there were soccer goalposts in the distance and lumbering women throwing shot put and javelin... After a few days in heaven, I realized that the javelin-throwers and the shot-putters and the boys who played basketball on the cracked blacktop were all in their own version of heaven. Theirs just fit with mine--didn't duplicate it precisely, but had a lot of the same things going on inside.
So... in the book, basically whatever you desire shows up in your heaven. Anything you want you can have right when you want it. Except for people. Not that there aren't other people in heaven, but you can't wish for specific people that you want to be in your heaven, like your family and people you loved back on earth. Susie finds herself separated from them, but she can still watch them (and eventually she finds that she can kind of interact/effect them). But she isn't really happy with heaven because she can't really have what she wants most, which is to be alive again and with her family (and for her murderer to be dead instead). The more I think about it, the more I think Alice Sebold's heaven sucks. I get that it serves the story, but still... call it something else if you're just going to make it this kind of after-life void that can't really support you. That's kind of lame.
The Merriam-Webster Dictionary definition that I think defines it best and I can agree with is this: the dwelling place of the Deity and the blessed dead; a spiritual state of everlasting communion with God
That's kind of general, but it sums up the idea that, hello, GOD is there. I think it's kind of weird to have a heaven and leave God out of it. At least have some sort of spiritual deity or something... I don't know. The book's view of it is just so... existential.
None of this means that I'm not enjoying the book thoroughly, I am, I just had some thoughts about the heaven stuff and thought I might as well share them here. Who knows, maybe I'll get farther in the book and she'll run into God on a stroll through her garden full of lollipops that she created. ;)
Totally psyched for the movie! Peter Jackson is a visionary.