I think it's strange when something is made out to be a childrens' book, but really isn't. Just now finished Ender's Game which was really good. It's the first of a series, but I've heard the rest aren't as good. (While I was at it I ordered the second one as well, so I guess I can tell you about that some other time). I had never heard about it, but apparently it's a classic (well, sort of). Reminded me of Player of Games. Maybe it was the subject... Player of Games had a more "adult" setting, but I remember the sex subplot getting on my nerves, it was so ostentatious (if that's the right word for it, can't describe properly what I mean - it was like Mr Banks hadn't been getting laid for ages and needed to compensate by writing).
Ender's Game, on the other hand, was quite sad. Melancholic, more. Matches the weather today (and my mood which is somewhat grey, don't know why exactly). I recommend it. The book, not my mood.
Now back to work.