How do they know the hottest toys for Christmas?

In anticipation of shopping for my little cousins, nephews and nieces, I want to avoid long lines and fights and find out what are the hottest toys for this year. Every year, on the news, there is a report on the hottest toy and they cut to some toy store that is all sold out and they talk about 4-5x multiple retail prices on ebay. Such examples are: Cabbage Patch Kids (never heard of them until my mom almost got into a fight over one); Furbys (I saw that coming), Thomas the Train (huh?), and I guess the original NES. Was it last year that Thomas the Train was so popular? Who saw this coming? Anyway, I’m out of ideas and my parents relatives aren’t very forthcoming. I’m looking for something that isn’t a Barbie or a game system, and is as hot as the examples I mentioned above. Any ideas?