I've recently started leveling a shammy. I must say it's alot of fun.
The stuff i absolutely love for leveling
a] 15 minute Hearth [astral recall] ! [and you still have your regular hearth stone with a seperate cooldown]
b] Ghostwolf at lvl 20 [identical to Druid's Travelform which they only get lvl 30....]
c] Water walking [i actually prefer this to druid's sealform ]
d] Water breathing [also better than druid's sealform as i can actually fight under water]
e] Stoneclaw Totem [fighting multiple mobs this is still pretty awesome]
f] Windfury + Duel Wield + StormStrike + Earth Shock [interupting spells + damage] = the shizzle!
g] Being able to wear mail, would be nice to have gotten plate too so Shammies could be semi decent at tanking [maybe in Wotlk?]
Anyhow i'm about lvl 50 now with my Shaman, compared to my Druid i'm kicking arse all over..including stupid rogues and warlocks underestimating a duel wielding windfury + grounding totem dropping shaman. So leveling is great great fun.
However most experienced shaman are telling me at lvl 50 i should probably just stop and leave it there as it goes downhill from there. I can already spot the signs:
a] Totems that reduce/increase [stuff] with a FIXED amount instead of a % of x . <--- those totems will NEVER EVER scale late game = great when you get them, but soon becomes pointless.
b] Having no CC/Stun abilities. You got like one "50% chance" totem [which again doesn't scale] which will be one-shotted late game i'm sure.
-> Even a druid who's not known as CC class in PvE got ALOT more CC ability [hibernate/root/cyclone/cat-maim/bear-stun/feral charge.....] . Shaman got ...errr...stoneclaw totem ??
c] No real "oh **** buttons" . Mage can iceblock,Druid can go bear,Hunter can feign death,Pallie can bubble,Warlock/Priests can fear,Warriors well i'm sure they got something like spell reflect

. Shaman got....? Up to now [lvl 50] all i have is instant ghostwolf and earthbind totem , which is very situational to use.
d] I don't know if it's just me, but look at the talent trees and you might notice ALOT of skills does not give -you- [the shaman] ANYTHING. It gives stuff "to your party" . I kinda
expected that if i take the trouble to enchant my weapons with something [using an entirely different shaman spell] -AND- drop a totem doing the same, that somewhere i should get a benefit? (especially if use talent points for it...) I just sense a heap of redundancy there.
-> I'm specifically talking about Windfury [TOTEM] vs Windfury [WEAPON] . The shaman will always use Windfury [WEAPON] , as it's just a weapon enchant you cast on both weapons...if you drop the Totem you get zilch from it. Catch is you need to improve the totem [which you as shaman will never use on self] with a totally different talent than the spell you cast on yourself??! Am i missing something?
-> I compare this say the druid talent buffs [i.e. 5% crit], the druid ALSO gets it, it's not like the druid gets ANOTHER spell to give him 5% crit -and- then need to spend more talents to give the same buff to the rest of the party....huh?