I'm personally not a fan of Baby Einstein. There's too much research that supports that it's not making babies any smarter, and possibly making them dumber.
Every study I read says about the same thing, any kinds under 2 shouldn't be watching much TV, because it can actually bring their speech level down.
We are not really a "leave-the-TV-on" household, and we believe that you shouldn't completely substitute parent-child learning with TV shows.