Allow me a moment of dancing.
I really enjoyed the premiere. It really picked up well from where things left off, has given us a hefty pile of WTF to deal with in the alt-flashes, and they've actually started doling out answers, in their own fashion.
It also confirmed my long-held belief that Richard was aboard the Black Rock. Well, not exactly, but what else could NotLocke's comment have meant?
We get to see the temple, we get Hurley's abilities actually being important to the plot, and we get a hint of maybe, just maybe why the island can do what it does; it's in the water. There's more to that story, surely, but it's a start.
I love how central the Swan is to the show. It was a major plot point of the first season, it practically WAS the second season, it brought down the plane, and it took some time off in the third and fourth seasons with a few glimpses, but was back as a major plot last season, and we got to see it one more/last time this year, such as it was.
I would guess with Jacob's death, whatever he is, whatever he does, also affects the Spring at the Temple, and while some lingering effects remain, they are much dilluted, not as potent, and thus why Sayid's time in the spring wasn't enough/caused a delayed reaction.
Sawyer's rage over Juliet's sacrifice being for nothing is pretty much the exact reason why I felt they couldn't just do a 'we changed nothing' story, and I'm glad to see James as the voice of that side of things. It puts him right back squarely opposite and antagonistic to Jack, right where he should be.
I'm sure there is tons of other stuff worth mulling over, but I'm still processing. Add your own talking points, dive right in!