Ok well it didn't take long for me to finally become the latest victim of this BS. Got my card early December after black friday sale...SanDisk 32gb ultra. Last night shortly after I finished recording a video, all of a sudden it started giving me that "blank SD card" message everyone on this thread is quite familiar with now.
Card is still able to read by my PCs, and I put it into my gf's S2 this morning and it was reading the card just fine as well. It's back in my phone now...and it's sporadically cutting in and out...being able to read the card for a while and then not.
I'll be getting in touch with Samsung shortly