This is cool!  I haven't seen the Snowmen yet but I look forward to it, especially now.  I like the new layout, and the ladies interest in souffles caught my attention, apparently there is a connection between her and her character inside the Dalek, and The Doctor noticed it too.

Yeah the new openning credits look way better than colonoscopy version used in the last two seasons. I love the llittle nod to classic series credits witht a glimpse of the Doc's face in the cloud.

Oh my God!  You killed Clara!

You bastards!

woo hoo!! classic looking Cybermen! Can't wait to see where this season goes. Love the additions of Lady Vashta, Jenny Flint, & Strax as the supporting crew. Although didn't Strax die in "A Good Man Goes to War?"

Yes, Strax died.  They even mention it in the episode.  He got better, probably using the same tech being used to try and save Clara.  The Sontarans, being a race bioengineered for war, would presumably be designed to be easily repairable.  One of these days, they really need to do a proper origin of the Sontarans.  We have an official origin story for the Daleks, Cybermen, Silurians, Sea Devils and Ice Warriors, but not the Sontarans.  All we have are the stuff from the old Doctor Who RPG, novels and comics.

Wyldstaar, they do have an origin story, very similar to the Daleks but not as malevolent.  The original Sontaran race was in a millenia-long war with a neighboring species, the Rutan Host, and created the the modern Sontarans, mass-produced genetically engineered clonal warriors to fight for them.  Not long after the original race was wiped out leaving the warriors to continue the fight.  Sadly the war still continues, lasting for the past 50,000 years, the Rutans having apparently adapted as well, both stuck in perpetual stalemate.  The Rutans only appeared once, in the original series, shapeshifting amphibious jellyfish.  Personally I think it's past time for them to make another appearance.

I appreciate the attempted assist FJ, but most of that is from the old Doctor Who RPG, novels and comics I already mentioned.  Their neverending war with the Rutans was established in the classic series, and that they are a race of clones.  How that state of affairs came to be has never been addressed in an episode.  The expanded universe stories regarding the Sontarans vary.  Some of them are as you described.  Others indicate that they are all clones of General Sontar, a meglomaniac who destroyed his own species in order to replace it will a civilization consisting entirely of clones of himself.