(This update may still be in the process of being pushed out to all trainers.)
It has been discovered that, when traded, Pokémon have a chance of becoming Lucky! Lucky Pokémon will become sparkly and require less Stardust to power up. It is said that the longer a Pokémon spends in storage, the higher chance of it becoming a Lucky Pokémon.
Also with this new update comes the ability to nickname and sort those on your friend list.