Righteous Fire (Level 81): 1.5 sec cast, 30y range, no cooldown. Deals holyfire damage to a single target(and possible additional effect depending on talents. This is a standard bolt-type dmg spell, except that it is dual school).
The reasoning:
Ret wants a new dmg button to push - righteous fire will be made instant cast by art of war.
Prot is getting it's aoe dmg/threat nerfed - a new single target ability to compensate is in order. A prot talent give shield of the righteous or something the chance make righteous fire instant cast, so mix up the prot 9-6 rotations somewhat, a little bit like the warrior talent sword-and-board.
Holy finally, is the only healing class left in the game without a offensive spell to depending themselves with (smite, lb, wrath. Holy shock does not count - it's a 6 sec CD *healing* spell). In addition, a holy talent should get massive boost to exorcism spell-power co-efficent baked on to it, to make this spell scale properly for holy paladins.
Insert Name for AoE heal Here (Level 83): There should be little doubt left that paladins will recieve aoe heal in some form now. In addition, will of course most likely recieve a new direct heal filling the role a downranked Holy Light used to fill in TBC.
For the Level 85 ultimate spell, I would predict either a mobility spell (which warriors got) or a spell defense ability (which DKs got). Druids, interestingly enough got both.
The question has been how to give paladins mobility without (again) recycling old ideas already in use by other classes.
I think I have the answer to a paladin-flavored mobility spell, however...
Summon Charger (Level 85): I've always said paladins don't need a charge. What need is a Charger. Our charger.
This spell summons the paladin mount in combat, giving that extra mobility we always wanted for x number of seconds.
Bonus points to Blizzard if they make it possible for us to attack and cast while mounted - few things should compare to striking down those lowly rogues and hunters while mounted on your horse. (Or Sun-blessed Kodo. Screw you, tauren).