Oversoul:
The card itself actually looks pretty good. So, what color is it anyway? If I cast Persecute naming white, does it get discarded?
Yes, it gets discarded. You can tell what color(s) a card simply by looking at what it takes to cast it from your hand. In the case of the card above, it contains W and R in its mana cost, meaning it is both W and R.
For me personally, I love the new gold card layout. It really gives the card its asethetic distinction while adding a tad bit of practicality for those of us just beginning to play the game.
The one thing that has got me so drooling in this set is the U/B Gild, which contains the Transmute ability. It seems that WotC is trying to hard to make a dominant U/B control deck. Transmute will prove very useful and playable as far as my casual gaming goes. If the environment slows down, which is a far strech now with the inclusion of the Elves, BoP, Sakura Tribe Elder, Kodama's Reach etc - Transmute may prove to be game breaking...
All in all, Ravnica seems to be shaping up like a favorite block of mine, seconded only by the all too flavorful Mercadian Masques (I know MM gets a lot of heat for being slow and boring, but...)...