Which is better? A shaman or a druid (in World of Warcraft)?

Better will be defined by your desires in WoW and your play style. Also, what do you plan to do with either class? PvP? PvE? Both?

I used to main an elemental shaman a year ago. About a week into the last PTR session, I was on WoW testing things daily from my shaman a year ago. The new LFG (now called DF;dungeon finder) really helped me gear her from her greens and blues after hitting 80 to getting the best heroic gear from 5-10 player instances. I leveled as enhancement from 1-70 pre-WOTLK. It was the most fun I have ever had in WoW because of the talents and how they worked in synergy with spell power. The talent that offered agility to get a certain percentage as spell power was so much fun because it was a bit overpowered but seriously helpful during leveling. I could heal level 12-60 as enhancement because I had so much agility and intellect. :) I don't ever play melee classes as I'm a strict caster player. That is why I had the most fun. HOWEVER, as of WOTLK, the talents have been changed and when I tried enhancement shamens at level 80 (premade) it was seriously boring to me because obviously I dislike playing melee characters. So that should say something about shamans coming from a caster play style.

Druids are very versatile. They are more of a master of almost all with more emphasis on ALMOST. Even though they are a jack of all trades, they trail very close behind those roles who specialize in specific only that role compared to the druid, who specifies in all three. Level as a balance druid as of the LATEST patch is more possible now. It may become just as fast as level as feral once Cataclysm comes out as intellect then will provide spell power and the spell power stat itself from items will be removed come the expansion. I hated leveling as a feral druid and I stopped a bit short of 60. This was pre-WOTLK. I also leveled a druid on the PTR to about level 40 purely doing quests as feral. Just as boring coming from someone who plays only casters.

I can't tell you which is better because that's like saying "apples are better because you can actually stomach the skin compared to oranges". They have their strengths and their weaknesses.

If you want versatility and mobility, go with druids. If you want a class meant to burst damage but, at the the same time keeps going and going when the rotation is changed, choose a shaman. You could argue the same for either side vice versa (shamen can be versatile and mobile/druids can do burst damage and keep going and going) BUT THEN YOU'RE ARGUING PERSONAL OPINIONS. It is made clear by Blizzard because of the spells and skills both class have. Bloodlust, clearly a groundbreaking DPS/HPS spell, for a shamans, a shaman's very definitive mana pool when healing, the fact that a druids HOTs are the most mana efficient HOTs in the game (ie Lifebloom, Rejuv talented, Regrowth glyphed) coupled with fact that tree form makes those HOTs work on par with a priest's, paladin's, and shaman's healing efficiency, and the fact that feral forms do not require mana to cast skills and spells.

A defining line that you should ultimately know is that a shaman's PvP ability is more limited compared to a druid's PvP ability across all fields (damage dealing, running away, healing, and survivability/taking damage). That is especially noticeable in arenas and with players, both friend and foe, who use a significant amount of resilience.

I was kind of disappointed with moonkin form. If I really wanted a caster I'd pick shaman of the two. Keep in mind that if you change your mind on how you want to play your class druids can be four different things. Shamans can never be tanks. Also consider warlocks. You're sacrificing more versatility but you get a permanent pet and near-immortality while leveling.

I have one of each. My druid is lvl 52 and my shaman is lvl 22. I didn't really enjoy playing my druid until she got over lvl 40 and went balance. She is rather fun now. My shaman I'm still not sure about her. Don't really enjoy playing her yet. I've seen other shaman in action and I'm like wow they're great. I'm not sure which is better but I prefer the druid.

Sniper in call of duty