Guide: Paladin - Holy

Not going to copy and paste here since the authors tend to keep them pretty updated.

Talents/Gems/Spells/etc:
http://elitistjerks.com/f76/t55577-holy_paladin_guide_3_1_a/
http://www.bananashoulders.com/2009/04/09/choosing-your-attributes/

Gear (Best in Slot guides):
http://www.plusheal.com/viewtopic.php?f=7&t=2639

Upcoming changes in patch 3.2 will change holy paladin gearing some:

They finally decided that stacking intellect + crit provided us with too much mana regen between Replenish and Illumination

Illumination - Returned mana down to 30% from 60%
Replenish - down from 1.25% every 5 seconds to 1% every 5 seconds
Mp5 - Mp5 on gear is being increased by 25%
Sacred Shield + Flash of Light - Flash of light on a target with SS will place a HoT on that target healing 100% of the amount healed over 12 seconds.
Beacon of Light - 60 yards range from 40 yards. Multiple paladins can beacon the same target. Overhealing will count toward beacon target.
Divine Intellect - Down t0 10% intellect increase from 15%

So with those changes it's very possible that Mp5 will surpass intellect and crit for mana regen and paladins will no longer be spam healers.

One note to make:
If you can get away with primarily flash of light spam (90% of my casts are still flash of light in Ulduar) for healing then you will still be hard pressed to run out of mana in current content even with these changes (might involve picking up some Mp5 gear to offset the illumination changes).