I’ve read about problems with the security of the TKIP encryption algorithm (and by extension WPA certification which uses TKIP). Why is this coming up now?
Security technology evolves over time. Encryption is based on mathematical algorithms and from a practical standpoint security is largely a function of the amount of time it takes to "crack" an encryption algorithm. As computing technology becomes more powerful, encryption standards that were the state of the art when they were introduced become vulnerable and are replaced by new standards.
The current discussion around the security of TKIP indicates that the risk to users is very small. However, security experts believe that the insights behind this attack on TKIP will lead to additional attacks that continue to erode TKIP protection.