If the latest rumors about Amazon's Kindle Fire 2 are true, it would mean that they are taking the new Nexus 7 seriously as a competitor and are attempting to come on strong. According to a report from China Times, Amazon has already ordered 2 Million of their 7-inch Kindle Fire 2's from Quanta and are poised to ship them on August 7th. This does seem to line up with some of our previous rumors of an official announcement coming on July 31st. Here's a quote from the UnWiredView article with some more details,

The new 7 Kindle Fire will have a metal frame, the rest of the chassis in plastic, with displays coming from LG and touch panels supplied by TPK.

No news about the 10 and 8.9 Kindle Fires yet, but they probably are coming too.
This summer and early fall is certainly shaping up to be a firestorm of new tablets.

Source: Kindle-FireForum via UnwiredView