Exactly. I don't get all the Avatar hate. The story was bad, but the cinematic experience was excellent. It was a summer blockbuster style movie. I didn't go into it expecting a plot, I went into it expecting action, explosions, and shiny things. It delivered superbly on those things. Don't judge Avatar against hard sci-fi, judge it against something like Star Wars or the new Star Trek movie. Its purpose was to entertain, not to leave you thinking about it for days. Personally, I find nothing wrong with that. I generally prefer movies like Primer, but sometimes it's nice to kick back with a bucket of popcorn and marvel at the pretty lights.
I found it impossible to relate to or care about any of the characters.
If you haven't seen it, find the incredible review of the Phantom Menace on YouTube by Red Letter Media. The most insightful part is where he asks people to describe the nature of the characters in both trilogies. For the original movies, people instantly recall, for example the "dashing...arrogant..scoundrel" Han Solo. For the newer films, nothing. What was princess Amidala like? Nobody cares.
Avatar suffered from this, and no amount of shiny graphics could ever bring me to care. With great characters you can forgive all kinds of things (eg Battlestar Galactica.)
I wouldn't call it lame. It's predictable, precisely because it's a fairly standard hero story, the kind we keep telling each other since we have learned to tell stories.
Stories like these are part of what makes us human.
