The veteran is a very rare (purple) officer who has two unique traits: Space Warfare Specialist, which provides a skill bonus to Starship Maneuvers, Starship Targeting Systems, Starship Energy Weapons, and Starship Projectile weapons; and Veteran, which grants a team bonus to damage, dodge, and avoidance.
Basically in the dilithium conversion, there are three categories, people who got all refined dilithium, people with more currency who get refined dilithium and dilithium ore and people who have so much currency that they can singlehandedly ruin the economy (allegedly) who will have half their ore 'discarded'.
The second two teirs will be getting an awesome boff which grants better maneuverability, better accuracy and better energy/kinetic damage
If I've done my calculations correctly and thanks to a warning from someone on OPvP last night not to spend all my emblems (just as I was deciding what to spend them on), I should be getting the "super boff" on both my main characters. Shame about the rest of my mid level characters that I haven't bothered levelling up though.
With some lack, my apathy over the past few weeks ensured that I still have all my Emblems and will now get the uber BOFF on most chars. Of course, I would then have to grind for Dilithium to gear up. But maybe my apathy can help avoid that, too. And besides... Deus Ex is waiting.
If I was being cynical, I could say that they deliberately left it to the last minute to announce this, in the hope that most people would spend their emblems beforehand (following the advice of several well known people) and thus not earn any of Cryptic's precious dilithium in the transfer...