I have Twenty Ten installed and have recently upgraded to 3.5 (although I can't confirm this started with the upgrade). I have a recent posts widget in the right side bar and the words are there, but they are no longer links. They used to be... a couple are still purple from being v-links when I tested initially. I tried theme Twenty Twelve (and changed nothing else) and the links work fine... weird huh?
Has anyone else had to deal with this? I'm going to DL and copy the theme manually into my server to see if that helps. If that doesn't fix it, I'm stumped... Anyone?