I think this is a form of homogenization that's not necessarily a bad thing. It's a "bring the player, not the class" thing. They're doing their best to remove raid stacking to ensure that every possible buff is provided. Granted, having Light and Wis up on the target wasn't really a huge deal (nor was it difficult to get two pallies to judge it) but it falls in line with that line of thinking.

The removal of Judgement of Wisdom is easy to understand--- they don't want people easily gaining that much mana in Cataclysm.

Think about how many ways a paladin has to regain mana himself, and to restore mana to his team. There's a reason pallies today are nigh unstoppable healing machines, even in a world where healers hardly ever run out of mana.

They simply want to reduce the amount of mana a paladin can get back and give back, otherwise in the Cataclysm world where mana matters, raids will be benching others for their token paladin. Or at least, I think that's the dev's fear.

One reason I'm sure that Seal+Judgements are taking back seat to Holy Power as our unique mechanic is that, at least in it's current implementation, not all specs get enough benefit out of Judgements. Ret paladins get the most, and Prot pallys have decent use for it as well, but especially for Holy Paladins it is an irritating mechanic to deal with for two reasons.
One - It's not really helpful on it's own but absolutely necessary to use. The healing from Judging Light, while nice, doesn't boost our healing all that much, since most of it will be overhealing. But we need to do it for the haste buff.
Two - Since Judgements are considered melee attacks, even though we as Holy Paladins have a 40 yd range, the GCD is still 1.5s after Judging. That means every time we Judge we have a longer wait before we can start pumping out heals again, in which time the tanks can dip dangerously low.