I don't think the tablet market is that big of a deal. This is still a toy with limited use. Bought an $80 Nokia 521 smart phone from HSN last week. WP8 is just as smooth and speedy as IOS for a fraction of the cost. Most of the popular apps for IOS are also available for WP8. Nokia 521 also comes with a world GPS map. Download the appropriate maps and use the phone as your portable GPS.
Most people don't use more than 10% of the capability of a smart phone. Nokia 521 links with windows 7/8 and also comes with free Skydrive. Reviews have been very good to excellent everywhere.
However, to Amazon is a big deal because it will have to keep selling its kindle HD at low price, probably lower than cost. Amazon cannot just discontinue Kindle tablet business because its one of the big revenue contributors, and big story of its media contents.