I still watch F1 live on SpeedChannel, I've been watching it live for 18 years now. However, I tend to miss a race or two here and there, and now it's no big deal. The nice thing about the early morning races is that nothing else intrudes on my time at 9am in the morning. My wife watches it live with me, too...so life is good enough to me!
I'll watch a little bit of anything non-NASCAR on Speed nowadays, especially the historic racing or the Legends of Motorsport. Tin tops, prototypes, a little bit of everything. but I rarely watch a whole event. I'm not as enthusiastic about NASCAR anymore, I might watch part of a race here and there. It just seems so much more "artificial" now.
I used to get into watching WRC on Speed; it's traditionally on so late at night (11pm), but since taking the job at Lexus, I'm in bed by 10 on weekdays, so there's no time for it anymore.
Basically, I watch TV now as filler between two other things to do; like waiting to leave somewhere in 15 minutes, phone call on hold, etc. I don't have the time I used to, when I'd watch racing on TV of all stripes all day long.