"Kaon Under Siege" a level 50 flashpoint — a smaller raid limited to a group of four — has been added to the game. Four bosses also have been added to "Karagga's Palace", which is an Operation or full-fledged raid.
Bug fixes, changes to the open world PvP on Ilum and a new tier for level 50 PvP warzones have also been added. The bug fixes include making some inaccessible datacrons accessible and removing glitches that blocked some characters from advancing in a conversation.
Full patch notes at the link.