Speccing Frostfire Orb DOES remove Flame Orb.
And would they move it to the Frost tree? It isn't Frost Orb. Frostfire spells go in the Fire tab apparently, like Frostfire Bolt.
There is currently a Frostfire Orb icon in game, you can see it if you look through the icons available when you are making a macro.
They also do have separate tooltips. You can see them on Wowhead.