Small update on the baby blackbird: it seems very happy in its cage. It chirps in greeting whenever somebody gets close to it, and chirp again when it wants to be fed (it's stopped screaming). Even when it's been fed, it'll latch on your finger (not to bite it) if you get it close to him.
It's so plump and well-fed it doesn't look like it'll take long for it to get to the growth stage where it can fly and we can let it go...