Bottom line: The Kindle Fire isn’t much of an iPad threat yet. The real trouble will be for companies like Barnes & Noble, RIM, and Samsung, which are trying to sell 7-inch tablets that either cost considerably more or have poorer content and apps ecosystems.
I think the price point is going to attract a lot of buyers. Amazon has been very careful to position this device as a Kindle, rather than a table - NOT an iPad competitor. For some, this will take the place of a tablet, but for the vast majority of buyers, I think this will serve as a companion device to their existing iPad.