my personal view... you can set a schedule for your baby and watch with him/her of coz. my son wathced YBCR from 5 months, initally, he can't concentrate, just 1 mins then no interest.... ok, then i turn it off.... everyday like this, then he start to like it... 1 min, 2 mins, ..... then he can watch the whole program. just once or max twice a day (one DVD). I think it is okay, cannot let him/her to watch too much per day, try to avoid to built up his/her interest to watch TV.
Now, my son is 1.5 yrs, we trun on the TV, he just watch about 10-15 mins then walk away to play/read books.
if we turn on the DVD/Cartoon, he has more interest to watch, if the program is finished and we turn off the TV, he is okay!