Yes, I have my LG 47" outputting to my NAD M51 dac and it sounds pretty good. 48k, I believe most TV's are going to give you stereo PCM via the TV's sample rate converter.
For example, CATV outputs 48k stereo PCM from the TV optical. However if I play a CD in my Blu Ray that is 44.1k and run it through HDMI into the TV and OPT out of the TV to my DAC it displays 48k..... the TV's DAC/ sample rate converter is always going to output 48k regardless of original sampling rate.
Don't know if it's that way with all TVs but that's what I've observed.