Well, I think Grey's get all the kudos due to their talking ability, but I suspect all parrots are quite intelligent. Rowdy is just a conure, but she is one of the smartest animals I've ever met. Her "knowledge" vocabulary is very big even if she doesn't say all these words all the time. The other day, knowing I can't say "dinner" or "veggies", I said something vague like, "I need to get your stuff", and she still knew what I said! And she has said some crazy things when she has felt the need to tell me something.
Had I not been working when I first got her, I probably would have started teaching her colors and shapes and things just because I was so impressed by Alex. Maybe I still will, lol! Although if I want them to say the words, Pete might be the best candidate. At this moment he is proving he can be quite a talker, saying new things all the time, and talking most of the day now.
I went to a party store yesterday and bought mine a bunch of random party favors. Little sparkly plastic chotchkis! When I give her a new one, I usually put it down next to her, then flip it around a bit and say "wow look at this cool thing!" and bat at it until she chomps it! Rarr! Wherever we are in the house, I look around for random stuff and hand it to her.