Well, with the mass complaints on the Beta Paladin forums something had to give:
We are still showing good healing from Holy paladins. However, we are getting feedback that they may be struggling with mana and perhaps even with boredom. To help with both of these potential problems, We are going to change Divine Plea to only reduce your healing by 20% (up from 100%). However, the original nerf to the spell was partially because of it being difficult to stop a paladin in PvP, so we are going to make the effect dispellable.
We're still taking a look at some of Holy's deep talents and I do want to acknowledge that there have been many great suggestions to change some of those.
We understand that some Holy paladins still feel that their movement and group healing mechanics aren't sufficient yet. However, we still like Bacon of Light , Holy Shock and talents like Infusion of Light to help with these problems. We want to get a few of the kinks out and see them in action more before making further changes here.
We also want to reiterate that measuring healing is much tougher than estimating dps or tank mitigation. While healing throughput and efficiency are important, so is knowing who to heal when and with what spell. We're going to keep a close eye on this through the rest of beta, in the Burning Crusade patch and when Lich King goes live.
Thank you, as always, for your feedback. (Source)
So, it was PvP that caused it to be nerfed after all. Well, I'm not surprised in this, but maybe a little disappointed. However for PvE the skill can now finally stand on its own two feet.
I'm still extremely concerned by how easy it is to dispell critical Paladin buffs in PvP, and how relatively difficult it is for us to dispell debuffs. I also feel that mobility and vulnerability to cast lock-out are big issues for PvP and PvE that can't be easily addressed by attempting to balance both. If nothing else, for Holy Paladin sanity alone Infusion of Light needs to be de-nerfed (perhaps by causing the casting cost to reduce by 2 secs, and thus you need to get at least one non-instant HL off in the preceeding 10 seconds to make it instant). The previous Holy Paladin incarnation, in just the last beta build, was fun and much more interactive than the TBC incarnation. Just not having to stand in one place to heal was a big step up, which in itself is a poor indictment of the TBC Paladin.
With the Beta swiftly coming to an end now (I'd predict only about a month left, maybe less) time for new abilities and mechanics has probably run out. As with the Hunter Aspect Mastery new talents will probably be re-visited after the mania of Nov. 13th, talents such as Prot's ever elusive 11pt talent or Aura Mastery being made baseline. The pressure on Blizzard to finalise things and send it off to QA for testing is getting palpable, and so we should all take a step back and elect to live broadly with what we have. Minor (or major) tweaks to what we have now is the order of the day, new skills and talents to address major shortfalls that players have identified but Blizzard hasn't will be seen only in 3.1.
EDIT: Siha at Banana Shoulders has a pretty good summary of events.