Gwen having a plot that's not about Arthur! Hooray!
Someone remembering that Gwen knows how to use a sword! Hooray!
Arthur being clever! Hooray!
I wish they'd explained how Gwen knew the people from the village, though - I'd assume she lived there before coming to Camelot, but last year they established that she's known Leon forever, and Leon didn't seem to have any connection to the place, so that doesn't work. And it seems weird that the guy would be the village elder if he weren't actually from the village and only moved there after living in Camelot and knowing Gwen. So that's all very mysterious.
So ... Gwaine/Elyan? What with Gwaine being the one to carry him, and stay with him while Leon and Percival ran off to look for Lamia? Iiinteresting. I remain saddened by the lack of Merlin/Gwaine this year; Gwaine still seems to care a bit, but Merlin doesn't so much, which is unfortunate. It's also a shame that this is the most focus we've had on the knights, and they spent pretty much the entire time not being themselves.
This series so far has been so much about Arthur's ridiculous love for Merlin that I, uh, think I actually forgot for a bit that he's supposed to be into Gwen. When he said they had to go looking for everyone because Guinevere was with them, I just went "Pffffffffffffft, sure, Arthur, it's Gwen that you're worried about. Riiiight." And that last scene between felt very strange and sort of inappropriate for a couple; it was basically Arthur and Gwen having the sort of interaction that Gaius and Merlin usually have at the end. Only with kissing. So that was weird. They really need to lose all this serious romantic nonsense and have more awkwardness and flailing with the two of them, they're so much better that way.
Really didn't need Arthur going on about how being saved by a girl is as bad as dying; I didn't mind when he was whinging over Morgana claiming she saved him back in series 1, because that was typical of them, but it just didn't work for me at this point, especially since a) he was being all proud of Gwen later and b) he was saved by Gwen himself back in series 2. I suppose it was more about giving Merlin a hard time than anything to do with Gwen or girls in general, but still, I'd rather they had done that some other way.
Also, I am totally taking that "You're a woman" "So?" exchange between Merlin and Gwen as confirmation that Gwen is into the ladies. Obviously she thinks it's weird that she hasn't been enchanted too because she likes pretty girls as much as any of the boys do.
Dear show, you've pretty much made all your leads Rather Gay whether you meant to or not; how about you give up on this heterosexual romance nonsense and just go with what you're good at? Gwen & Lancelot is fine I guess, but I'd still rather Gwen got a new girlfriend now that Morgana's not around.