I just finished "The Empress Advances" mission over the weekend and got so distracted by the Typhoons, I almost forgot to fight the battle! That is one cool looking ship, here's to hoping that one day she becomes available.
This is the official dev response from December 2012's Ask Cryptic.
"Q: (cylon74656) Will the Steamrunner Class be available for those of us who don?t play through Steam? And also, when will we see the Typhoon Class playable in-game?
The Typhoon Class is a dreadnaught that will most likely not appear as a playable ship until we increase the skill point cap to full Admiral. Even then, we haven't yet decided if this will be a player ship, but we can be convinced to make it so if there is enough support for it."