Druid or Priest, which healer to pick?

I've searched but none of the posts seem to answer my question.
I'm very soon to be 60 and have a decision to make; do i keep my druid, which has been in cat form and transformed back when healings needed, and spec it resto for outland/northrend instances? Or do i introduce a 60 priest?
Which is a better healer for my 4 paladin team?
Does a priest out heal a druid in tree form?
Help please as i have never healed over lvl 60.
Thanks
-H

Tough question when it comes to healing both are quite capable. They both have a decent aoe heal and nice buffs.

Although healing with a druid is more pro-active ,as in yeh gotta drop the hots before yeh get low, where as a priest its more reactive. Not that big of a deal just something yeh gotta realize.

I ended up picking a druid havent had any issues with healing.

They both have advantages and drawbacks. Priests are more reactional healers than druids, you either prevent damage from happening, or you heal afterwards, whereas druids need to pre heal before the damage hits, keeping rolling HoTs on the tank, and on the group for aoe heavy fights. It all comes down to preference. Id go priest just for the buff, the stam buff alone is quote powerful.

When you're off-spec, a Discipline priest is of far more value to 4x pallies than a moonkin (although the spell crit is cool) or cat.

Well I can't talk about a 4 paladin + healer team, but you can see my mixed team in my sig.

I recently switched from using my druid as a healer to using my priest (specced holy), and I must say, although I loved the hots of my druid for heroics my priest does the job better.

This isn't because of tank healing, both could keep up my tank quite easily, but where a holy priest realy shines is group-healing.

For group healing with my holy priest I realy love the glyphed holy nova, its so good (even after the glyph was nerved) that some fights get realy trival (like the elemental/kollosus in Gundrak or Novos in Drak). Other than this, the priest brings Prayer of Mending to the table, which I rarely use (because my tank often is the only one in range), but for your 4-pally-group it is quite a nice tool :)

And don't forget, that a priest can supply a -10% physical dmg buff via Inspiration, which a druid can't.

So all in all,I never regret changing my druid to moonkin and my priest to holy, as it improved my performance in heroics quite a lot.

Tough call.

They both bring strong buffs, can both rez.
Both heal fine single and aoe.

Druids are HoT based, so you'd like to keep the HoT's rolling and precast.
They are impacted less by movement encounters since HoT's are instant cast except for Regrowth.
Nature's Swiftness, Innervate and Battle Rez are extra for them.

Priests (Disc) can bring a ton of mitigation to the mix.
If you're not using a click castsequence to automatically apply HoT's, they're probably easier to box.
PW: Shield, Holy Nova, Pain Suppression, Power Infusion are some of their extra's.