I'm a big fan of Colin Percival's "Cryptographic Right Answers" post.
This was written in 2009, which is a long time ago in Internet years.
Is the advice still valid or, if not, can someone point me to more up-to-date information?
For the clearly cryptographic recommendations:
So none of it is bad advice even after seven years.
By and large, his advice remains good.
I spotted only two recommendations where I would have a slightly different recommendation:
I disagree with his advice about client-server application security. My recommendation would be to use TLS, and just use it properly. I understand his concerns (it is complex), but my experience is that when developer build their own protocol for client-server application security, they tend to introduce security problems -- and my sense is that the frequency of that kind of failure mode is higher than the frequency with which serious bugs are found in SSL code.
For encrypting data, today I would recommend using authenticated encryption (e.g., AES-GCM or EAX or a similar scheme), because it's slightly easier to use -- but there's nothing wrong with his suggestion of Encrypt-then-MAC using AES-CTR and SHA256-HMAC.
(His argument against using authenticated encryption schemes is that they are new, complicated, and rarely-used. That might have been valid in 2009, but I don't think it's as valid or persuasive today. So that's one spot where my advice would differ from his article.)