I haven't seen them for some time either. I don't know if they're gone for good, but with the FCC finally setting a deadline for analog TV (even though it's still a few years down the road), it's days as a pseudo-LPFM were numbered, so perhaps they're moving to a real LPFM.
If so, it leaves the VHF-Lo band vacant in DFW unless/until KSFW lights up.