Yeah, I think if you are going to have your babe watch TV then they aren't the worst choice. But it's best nto to put them in front of the TV at all! And I feel like the whole educational aspect is just a way to help parents not feel guilty that their baby is watching tv, ykwim?
Having said all that, I did buy my dd a book by them. I liked it because it had alot of art in it, well known paintings etc. and I thought it seemed pretty nifty. At the very least, a book that didn't bore *me* to tears.
I think kids *can* learn alot from TV, but it's better if they learn it from you. Sesame St. (for example) can teach a kid their A-B-Cs and up vs down, but so can you. And if you teach it to your dc, well, then they have the added benefit of time with mommy or daddy!