The big prize is a Breen ship.
If you do the race thing daily you get 40 autographed Q pictures (which you can also buy via lobi, but why would you?). You need to do the race 25 times during the 35 day event in order to earn enough of the items to trade to some demented ferengi for a the ship.
Stats for the ship won't be released till tomorrow.
It's slightly weird, because they're calling it "Chel Grett Warships" but the npc versions the Chel Grett are cruisers. The "warpships" have a different name.
The NPC Chel Grett's seem to be sci-orientated ships, they have dual cannons but also use Subnucleonic Beam and Energy Siphon. But who knows if the NPC version's stats will have anything to do with the playable? We'll see tomorrow I guess...