Here's my spec and I absolutely love it:
http://www.worldofwarcraft.com/info/...51031500131051
It's a hot build with 19 in feral (I consider it 21 feral cause of the Furor and Omen of Clarity).
I also have 600+ spirit, and as soon as Nightbane cooperates 660+ spirit (drop the stupid staff already you big worthless fireball) fully buffed with kings.
You have to remember this is raid healing. So my part in a raid is keeping everyone alive and giving our tanks as much +healing as elfingly possible. That massive spirit makes up for loss of the moonkin regen talent, and the spirit +healing makes up for the loss of hte +25% intellect +healing talent. My roll is not to be the one spaming the tank and off tank, it's negating that ae damage.
Treeform slowness can be somewhat negated by Boar's Speed on boots. You just get used to being slow. It's hard when you're a druid getting used to being slow, that's one of the things that attracted me to druids in the first place, they were teh supposed speed classes. Them and hunters. It's cruel joke making treeform slow. Treeform is also fairly cheap mana wise and insta so you can deform and reform if you're in the middle of an ae very quickly.
I absolutely love my job in raids. In 25 mans my job is to keep EVERYONE alive. In Kara I can be one of the 2 primary healers as well. We usually take 2 spec'ed healers + one non-spec healing class. You get used to tree form and it's limitations, your guild just has to understand that if you're in treeform there is absolutely no way you can be the healer that spams a tank all night. You just can't do that in tree form. And pretty much every encounter has ae damage nowadays. If we do run into another Patchwork just go treeform and spam lower ranks regrowth. You wont top the list but your +healing from 3 pallies spaming the tank is worth a heck of alot more then you spaming healing touch.
In normal 5mans I never run out of mana and heal just fine in treeform the whole time. I rarely have to go into spaming healing touch mode. Heck most of the time I'm using /sleep emote or jumping around flaping my giant limbs.
In 5mans heroics I can main heal fine for most of the dungeon, I just dont go tree form most of the time. I stay out and use healing touch mixed with hitting a lifebloom on the idiot melee. I do admit I ask that we bring atleast one off spec, or main spec, hybrid healer. If we bring another main spec I go cat form and do the off-healing on the bosses and hard pulls. I've actually made a decent balance +damage suit for the trash as well so I just spam wraith and off-heal-hot on the tougher pulls.
For cat farming and cat pvp I do "OK". I'm no warlock that's for sure. I wish I had the time and motivation to grow a mage or something to farm my gold with. I've even MT with 16k ac and sub par 350def and 25%dodge the "minor level 70 normal" instances without trouble.