Mmm..well, I've got a level 60 druid and I've been all three specs.
FERAL
Feral spec if you like being frustrated and taking six hours to kill something (Dire bear form is sooo slow) and you still die quite a bit.
Kitty form at this time until new patch is basically useless. You take on too much damage and don't do enough dps to be useful.
BALANCE
A decent enough tree in it's own right I would suggest this tree until you get to level 60- it's great for critical strike-soloing. You run out of mana alot and hurricane is a sucky AOE unless your just trying to get aggro
Call it your "kill me now button" at level sixty you can get a trinket in UD strath called "Ramsteins lightning bolts" that does similiar damage-immediatley-no channeling required.
RESTORATION:
This branch is to be honest, in my mind, the only one worthwhile. It gives you two key things which will get you into the instances and groups. One: The ability to should "Healer Spec Druid" catches just about anyone's attention. Second- Nature's swiftness- This is the bomb in healing- with this little key you can save a raid, pull someone away from the edge of death- beyond even what a priest can do many times.
Then you get the large and quite useful innervate at the end of the tree. This is beyond useful, it's wonderful. Consider this. You've been popping heals and spells at a mob and yourself for ten minutes, your mana is out but your health is full. Any druid knows this is "Oh !@#$%^&*" moment. Innervate

No problem Instant mana bar. It's useful when partying with paladins, priests, mages and warlocks, add this to the ability to heal and many times you can outheal a priest with sheer mana.
I've healed full 10man raids alone to UD strath, Scarlet, and LBRS. With no priest, and no backup. If you want groups- groups meaning instances- then you want to go Restore spec, when you get to the higher levels you can get innervate and have a little extra- toss enough in feral to get feral charge- (go straight to it) then get enough in talents to get your moonfire and starfire crits on the balance side.
This makes for a damn good druid build, you can heal all day- have mana to last beyond a priest, can hit with your spells hard enough to take down even the most strigid of beasts, go bear and hit feral charge and stop something running away. This gives you every major advantage of each class. So you don't get the flashy useless Hurricane spell...Oil of Immolation does the same ammount of damage and is fairly inexpensive.
<----Fyrestormie