What's the big deal?
For starters, the patch will bring about a new playable race and mountable pets. Strangely, today's press release doesn't mention the new race by name, and instead says that it will "arrive with an entirely new player class" that uses summoning magic in some form, and "differ[s] significantly from [the] classes currently available." As for the new mount system, gPotato says that players may use their existing pets and may also deploy the mounts during battle. The expansion will include new pets as well, and we'll bring you more on all the New Origin content in the near future.