I've looked and didn't see any write ups or anything on this site.
This I believe only involves 08+ and for all imprezas, wrx, and sti. Basically what's happening if you already don't know is the firewall welds keeping our clutch brackets in place are rusting and breaking and causing creaking and popping noises whenever you depress and release your clutch pedal. It's all over wrxforums and haven't seen it here at all so I'm giving you all a little insight on it with some help on fixing this, resolving this, and helping push a recall through hopefully.
Here's a simple fix I found thanks to one of the guys on the other forum.
Clutch squeak fix without taking the whole dash apart (nut/bolt style)
And here is a little bit more info on it including a video and some guys from coleman law or whatever trying to get people to file their case numbers and what-not
Major Manufacturing Defect.
Hope this helps and gives some people insight if they haven't known already