A few things:
It's hard just to compare heal costs and numbers without looking at the whole package. Paladin heals tend to be expensive because so much of their healing costs no mana. Likewise, we don't balance around perfect Beacon transference, but you can't ignore it either.
If you look at how much paladins actually heal in a fight though, it should be pretty competitive with the other healers. I know that's not easy to look at right now on beta, but it will get easier once A) raids are open, B) we enable mods again, C) more theorycrafters conclude that we aren't fiddling with numbers so much so that their time isn't being wasted. (We aren't fiddling with numbers nearly so much, so maybe that will encourage some theorycrafters).
Remember though, that each healer is different. Example: Resto shaman look great on fights where everyone can cluster for Healing Rain and Chain Heal and any time everyone stays very wounded for very long.
Because paladins have so many mana-free heals, they actually can't subsist on fumes as long as other healers. If every healer decided just to cast their Holy Light equivalent and nothing else, paladins would go out of mana faster. Now there shouldn't be any situations where you really heal like that.
Two concerns that I think warrant us looking at further are the healing of Holy Radiance and the crit chance of Holy Shock. We nerfed Holy Radiance so that Light of Dawn can be stronger -- it feels weird when the "finisher" is puny compared to the "builder." On the other hand, healers don't always have the luxury to wait for the finisher before doing some heavy healing. We've heard a lot of feedback that Holy Radiance is a little weak, so we'll take a look at it.
As far as Holy Shock goes, it did suffer from the pruning of many of the passive talents and glyphs that gave it such a high crit rate. In a vacuum, it doesn't need a high crit chance. It is an instant, relatively cheap heal that delivers on Holy Power. You're going to want to push it. But we agree that Infusion of Light is intended to help mix up what heals you cast and that it needs to proc at a reasonable rate.
I would encourage you all to go and read this forum as it contains a lot of relevant information regarding where things stand currently. As for me, I am going to take a wait and see approach with our healing. It has been my experience, that we Holy Paladins, tend to have to completely learn a new style of healing every expansion., and so right now this is just par for the course. If I were to be concerned about anything it would be our longevity. As GC stated, our spells tend to cost quite a bit (and with good cause), but with the current amount of mana regeneration I am unsure if we will be able to comfortably heal tanks at the beginning of the next expansion. I do believe though that for the time being, we need to not rage on the forums, but rather supply our genuine concerns and feedback to the design team. After that, all we can do is wait and see.