We've talked about the most recent changes on the PTR here and here. As of right now these are the changes we're working from in terms of speculating about what the class will look like in 3.1. It's fairly clear that most of the changes are aimed either at shaman viability in PvP. I'm disappointed to see that Frozen Power, the talent aimed at giving shamans a snare/root in PvP is 25 points down the enhancement tree, but not surprised, as it seems to be aimed more at giving enhancement shamans an anti-kite than in giving other shamans a kiting ability.
To be honest, none of these changes really makes me want to take an elemental or enhancement shaman into PvP. They're incremental improvements, changes that could in the future form the basis for something exciting for shamans (the new Glyph of Stoneclaw Totem has real potential, even though yes, it does use up your earth totem so that you can't be fear immune when you use it... this is and has always been a drawback of shamans in PvP and I don't think Blizzard is ever going to entirely remove it, although with Frozen Power you at least have a replacement for Earthbind) but at present it still feels somewhat unexciting. The way the changes affect PvE seems more positive, which is odd in a patch aimed at PvP tweaks for the class.
The change to Spirit Weapons, for instance, is an unabashed buff for PvE enhancement in a way that the change to Toughness fails to be for PvP. Yes, 10% more stamina is probably a better choice for a PvP enhancement shaman than the armor from current Toughness. It will allow you to survive one or two more hits from a caster. But in terms of how the changes affect how you spec, the Spirit Weapons change is going to immediately grab any shaman who intends to do PvE content (especially in raids) while you'll probably take Toughness begrudgingly and wish it had some further benefit.
Likewise, I'm glad they folded the current Improved Stormstrike into Stormstrike. But the new Improved Stormstrike seems half-finished to me. On the one hand, I never say no to mana return. Fully talented, you'll get 20% of your base mana back on every SS. It's not earth shattering, but it is a pretty solid mana conservation talent when combined with Water Shield and Shamanistic Rage. At the same time, I do wonder why we're spending two talent points for 20% of base mana (base, mind you... take off all your gear and look at your mana pool, that's what you'll be getting 20% of, I drop down to about 6k mana when I'm nude) - couldn't this just be a 1 point talent? Perhaps I want too much.
The Unleashed Rage change is good. At 3 points, you'll have 3% more agility and will add 10% raid/party AP. It's true that shamans still have to pay 1 more point for the same raid benefit that DK's get for 2 with Abomination's Might. Still, with the extra point in UR, we'll get 1% more agility and thus 1% more AP. I don't really know why the decision was made to make us pay more for the AP buff but get more from the stat portion of the talent, I guess it's a bribe for putting up with the added talent investment. And the Feral Spirit glyph is just awesome for PvE and PvP alike. More damage is always good. Getting more AP from UR and then giving more of that AP to the Feral Spirits? Yes please.
As far as changes for PvP elemental shamans are concerned, one of the real issues is how deep into enhancement they are. Toughness is 15 points in, Frozen Power is practically unreachable at 25 points in. So you're almost certainly not going to get Frozen Power, meaning that an elemental shaman still is vulnerable to snares and roots with no really significant way to get to range if caught by melee outside of Thunderstorm. Yes, there's Booming Echoes, which reduces the cooldown on your frost shock by a second, but that seems remarkably thin gruel for the PvP elemental shamans among us. Glyphing Thunderstorm to reduce the cast time by 7 seconds still leaves you with 38 seconds of basically trying to Frost Shock kite, which isn't going to work on, say, a rogue, warrior, DK or paladin, or feral druid... which means that elemental shamans can basically enjoy trying to frost shock kite enhancement shamans, who will then use Frozen Power to root them in place and very slowly walk at them.
Or you can cast Hex on each other and then trinket out of it for some laughs, I suppose. The new glyph means it would have taken more damage before it broke! Since Hex is poor CC at best in PvP (it's much nicer in PvE, especially in five mans) the overall effect of these changes for elemental is basically "You can get some more health, yeah, and you can get a damage shield if you don't mind being fearable and losing your Earthbind totem so that melee have an even easier time catching up to you." If they're really serious about improving shaman viability in PvP, elemental needs a trick or two aimed its way, I think. Personally, I'm still pulling for Sentry Totem. Glyph of Sentry Totem lets you actually switch places with your Sentry Totem? No? No, probably not. Poor, poor Sentry Totem.
Restoration shamans get a nice change with Ancestral Awakening now taking overheal into account. Again, it's not going to make shamans imba healers, but topping off the tank will no longer make you snarl in frustration as you overheal him by 2k and see a tiny little AA proc on the rogue who immediately dies to a firey cleave or some mysterious death spot on the floor. The new glyphs for Riptide and Earth Shield are nice as well, nothing to complain about there. Resto didn't really get much attention for PvP viability but since it's probably the most popular PvP spec for shamans it didn't really need any.
Overall I'd say that enhancement got some good PvE oriented changes, some okay PvP ones that we'll need to see in action, and that elemental didn't really get much of anything. Resto got a small but nice bit of affection with the new glyphs and the change to AA. I'm cautiously optimistic (very cautiously) that there are nice changes for elemental PvP coming, because that's where I'm most concerned right now.