Niantic has confirmed that post-Gen I Pokemon will be added to Pokemon GO in a future update.
If you've been enjoing Pokemon GO, but have noticed it is lacking some of the features of the main series games, you'll be pleased to know that Niantic has confirmed at at Comic Con 2016 that future updates to the game will bring the much requested trading feature, and additional Pokemon past the "Gen I" 151.
New Pokemon are still a while away, and while trading is a feature that is currently being worked on, it's not a super high priority at the moment, as Niantic is working their butts off just to keep the servers up.
"I'm sorry, I don't have a date for you [for trading,]" Niantic's John Hanke said. "We're working really hard to keep the servers up and running... It's at the top of our priority list."
Additionally, "Pokemon Centers," and PokeStop customization are also things the developer is working on. Hanke said that PokeStop customization would allow players to build up an area and use items to change PokeStop functionality.