I had the baby blues after my first bio boy was born. It took me almost 3 weeks to feel that "love-connection" and enjoy being his mum. With number two the maternal love was there instantly. I wasn't so overwhelmed with the responsibility and positive or negative sides to being a parent either. I think that's what helped.
I have read that PADS is just as normal as getting a depression after having bio kids. But personally I think PADS can strike you even harder since the longer you have waited, the more you have tried, tho more rosy-red picture of parenthood you'll have.
Kids are kids. Sometimes you wish you didn't have the responsibility of kids with their tantrums and nightmares and bad behavour to get attention, but then you have all the positive things, the hugs and kisses, watching them learn about the world or ride a bike for the first time as well, that you'ld never be without. It is very important to remember that having a child is hard work, but will give great rewards too.
I think Adoption agencies should inform about PADS and if there's not enough information about it, it would be good to contact the agencies and demand it. It should be in their best interest to have adoptive families as prepared as possible. We are talking about poeple, and their
families 
(As you can tell, I haven't started the adoption process yet, still waiting to turn 30, so I wasn't aware of the lack of information about PADS.)