I've only met 1 priest through all of BC that ever spec'd lightwell and he did it as a joke. Its been buffed to the point where it's... still useless.
The closest contender in my mind would be vigor, especially with the new energy regen system, or maybe premeditation, but even that works well with the new sub tree 51 point talent. I'm sure some pallies feel that holy shock is useless, but their aren't videos of people getting 1800+ arena ratings using lightwell.
The priest holy tree has 0 talents changed in the 1-41 point area. No other class has that honor. Thanks Blizzard <3