" Expect a few surprises between these Game Updates, too. You never know when the Republic might strike Dromund Kaas, if a mysterious alien fleet could appear in the Core Worlds… or when the Rakghoul plague of Taris might infect the rest of the Galaxy. Changes are coming, and they’ll affect everyone."
This is from the community blog.
We have the rakghouls already.
As for the alien fleet i really want to see some Vagaari, Nagai, Tof, SSi Ruuvi or Rakata to show up..
I would also love a pilot class with costumisable ship and better space mechanics. Building up my own wing ala Havoc squad with companions would be nice.