Are these emerging threats against AES affecting your designs? Recentally, an attack on AES was discovered which reduces its computationally complexity,  by a very slight amount.


The first key recovery attack on the full AES-128 with computational
complexity $2^{126.1}$.
The first key recovery attack on the full AES-192 with computational
complexity $2^{189.7}$.
The first key recovery attack on the full AES-256 with computational
complexity $2^{254.4}$.


There is also the new AES-NI instruction set, which allows attackers to make hundreds of billions of parallel guesses per day.  

In light of these emerging threats, have you made changes to your designs to mitigate the impact?  If so,  what has changed?
No, an attack on AES-128 requiring $2^{126.1}$ computations and $2^{88}$ bytes of known plaintext is not a concern. Brute-force guessing of keys (e.g., using the AES-NI instructions you mentioned) will succeed in $2^{127}$ computations on average and requires negligible known plaintext. Part of why key lengths are selected conservatively is precisely to ensure a safety margin which renders these tiny differences insignificant.

What the paper presents is an interesting method of analyzing block ciphers using a technique developed for analyzing hash functions. That this novel cryptanalysis technique fails to improve on brute force by even a full bit confirms the fundamental soundness and resiliency of AES's design.

Still, this technique is new and the paper explores multiple approaches to applying it. Cryptographers will be watching with interest to see if anyone goes farther with it, either through refinement or in combination with other cryptanalytic techniques.

Edit: In other discussion it was pointed out that this attack succeeds with probability 1, so an apples-to-apples comparison would be with worst-case brute force at $2^{128}$. It would be an exceedingly unlucky attacker who actually paid worst-case cost! A comparison of the typical scenario seems more relevant. The average-case for this AES-attack is probably a bit better than $2^{126.1}$, but it's not obvious from the paper. Still, the difference seems likely to be under a couple of bits (for now), while brute force retains its overriding advantage of not requiring $2^{88}$ data.

Of course one can build a weak protocol (or use a non-weak protocol in a weak way) on top of AES-128. WPA2-PSK can usually broken quite easily, because the pre-shared key is derived from a user-given password, which can be brute-forced in a short time. Even changing to an algorithm with a 10000-bit key would not help, if this key is derived from a weak password.