welcome to the life with a GGC....

they are lovable, cute and cuddly... and then there's the other side.... the beak side, i'm talking about....
valo has his days as well.... generally he leaves me alone and takes it out on my friends and BF, but recently with pita around he's jealous and doesn't get the time he's used to, and he's given me some good bites....
give him some time and space as leigh said... and be more careful when you handle him - when valo has those days, i usually do some step-up training, let him play on his gyms and keep him occupied when he's with me (like making food, cleaning up, etc) so he has something to look at instead of chewing on my neck...
it also helps to take them out of their usual environment - i take him for a walk in the hallway, which usually helps a lot... since you just got pickles it might also just be the change in home and lifestyle that will trouble him a little bit at the beginning... give him some time to get used to everything, but the above things usually work.... oh, and i give valo the "evil eye" and tell him "no" when he does attack... that works well with him too.... (if pickles is clipped a little time out on the floor could work for you as well... valo's flighted so that option is out for me)
good luck, and let us know how it goes! don't worry, he'll be fine once you guys are more used to each other... but GCC do have the reputation of being nippy, so you might have to find a way to deal with his moods... nevertheless, i wouldn't trade valo for ANYTHING - he's the best and the love of my life