I have installed the latest hddtemp 0.3-beta15.52 and lm-sensors 1:3.3.3 everything was fine in 13.04 Raring, but after upgrade hdd temp isn't showing. I'm using Hardware sensors indicator. I've tried with psensors but the same thing here.
Yesterday, noticed that hddtemp tool in the terminal shows my hdd temp correct. Maybe hardware system indicator doesn't pull correct this temp and needs to be updated for Saucy.