It's just happened to me as well. My long time pal 8GB Kingston sdcard got corrupted on Monday, salvaged the contents, put a new Sandisk 8GB memory card, formatted from device options, started transferring about 5 GB of music (drag and drop USB mode), 20 seconds before completion it stopped, complaining about data corruption, and media card was, indeed, corrupted.
Formated again (same Sandisk card), transferred music, bit by bit, again, but decided to turn everything off (carrier, wifi, bluetooth) and this time it seemed to go alright. Maybe the catch is that many applications were simultaneously writing to the sdcard, and receiving (logging) messages thru BBM/Whatsapp, didn't go well.
Just to be on the safe track, I'll point the device to save pictures and log events to the internal memory, and leave the sdcard only for music and save videos, which is what I mostly use...
Regards!