Don't get me wrong, I've played a lot of Shaman and tried to get it to work (mostly a quicker Midrange variant), but the inconsistent card draw combined with decreasing relevance of Feral Spirits and such makes it a much weaker deck than most of the meta right now.
With that said, I'm running a bastardization of Combo Warlock and Zoo right now that is particularly weak against early AoE (Lightning Storm). It's a weird list that I'm tweaking, which is part of the reason for my frustration at running into a fairly unpopular deck that can simply win with Lightning Storm unless I get the Eggs out.
I've played 50 matches with a tempo based shaman and so far holding slightly above a 65% win rate. This deck I made immediately after I got the BRM cards, I feel is a testament that Shaman is finding its way back to its pre-gvg roots of being a pretty good powerhouse on ladder. And the meta feels ripe for it. In fact, whenever priest is low count in the meta, I feel pretty good about shaman.
Druid: 50% 3-3 As I work out the kinks and include fireguard destroyer, this match up will definitely improve. How is druid gonna deal with a 4-7/6 hp minion on turn 4? Like wow, amazing. I think shaman is actually favored in this match up because of cards like crackle and hex. In a heavy druid meta, whether it is ramp or fast druid, I think shaman is good.
hunter: 50% 3-3 (feral spirits... so good in this match up and this particular deck can race even face hunters due to it)
mage: 90% 10-1, this is because there is a lot of tempo mages and the mech mage match up really isn't that bad at all. Earthshock, lightning storm, crackle, rockbiter... all amazing anti-mech mage cards. Key to the match up is avoiding really good turns where blastmage can kill you, which really isn't that hard between the above, haunted creeper, and flametongue totem.
paladin: 33% 2-4, here I think these numbers are not representative of the match up. I haven't played the match up enough I think. When I learned shaman in the naxx era, paladin wasn't even played much so I can honestly say that I am losing because of poor mulligan choices and maybe even some decisions. The problem appears to be paladin running zombie chows and shielded minibots and they are much more proactive than they used to be. My deck can become more proactive as well and I can learn a lot about the match up to win more. The main 2 problems are their early board presence and fear of quartermaster.
priest: 40% 2-4 Priest is definitely, and historically, one of the harder match ups for shaman to overcome.
Rogue: 50% 2-2 I'm gonna ignore this stat mostly for now. Mainly because they were all mill rogues. Not that mill rogues are going to vanish, although they might (no pun intended), but because its just too new of a match up and I don't know what to think of it yet. Frankly, I think I am favored and my losses can be attributed to assuming my opponents were oil rogue and I am mulliganing poorly. Damn you harrison jones! And damn you deathlord for getting my single mana tide totem (the mana tide totem literally cost me the game).
Shaman: 1-0 I think I am favored in the mech shaman match up, although these stats clearly are the most underdeveloped. To be seen.
Warrior: 100% 8-0 Unless the warrior somehow gets board control early on, I almost always win this match up. And the grim patron deck isn't doing warrior any favors in the match up since by that time I just lightning storm with spellpower.
Warlock: 75% 3-1 I think all forms of warlock is not favored against shaman. Shaman has a lot of early removal for zoo and can make it very difficult to pull a big wombo combo off with totems and feral spirits. Plus being a wombo combo deck myself, I think my combos come out much faster which means the warlock deck is usually on the defensive. Having earthshock ensures I can get by a taunt or two and hex takes out the a lot of high cost minions providing high tempo swings. For zoo, earthshock deals with eggs and lightning steam generally deals with everything else. Hex deals with doomguards. Zoo has changed a bit so maybe my opinion will change as I haven't played against it enough. The 1 loss was in fact due to zoo, but damn he was lucky with having tapped into a second implosion and I didn't get either of my feral spirits or alakir.