Originally posted here by Winston

The weakness is in the implementation, and provided you have a large enough sample of packets, the key can be retrieved in under a minute. Assuming you have 5-6 million packets captured.
The point of the article is that 5 or 6 million packets is no longer necessary. That is the number required by airsnort to generate the few thousand packets with weak IVs. With aircrack, only a few hundred thousand packets are needed, and they need only have unique IVs, which are far easier to come by. In other words, the time to crack a key just got much, much lower. This not only affects large companies with a lot of traffic, it also opens up home users (low traffic) to much easier attacks.