Some of your stuff makes me shiver, but XX and Mumford (and to some extent Edward Sharpe, though he's a bit of a douche) make me excited.
Elvis Perkins in Dearland - Shampoo
http://www.youtube.com/watch?v=J8DrwMNMBIU
Stornoway - Gondwanaland
http://soundcloud.com/ngower/stornoway-gondwanaland
The Twilight Sad - And She Would Darken The Memory
http://www.youtube.com/watch?v=QBHnESrmmM0
The Tallest Man On Earth - King of Spain
http://www.youtube.com/watch?v=ulKPDPSDNSc
Basia Bulat - Gold Rush
http://www.youtube.com/watch?v=hANYD0_qQl4
Mariee Sioux - Wild Eyes
http://www.youtube.com/watch?v=28yuWPnX33w
Frightened Rabbit - The Twist
http://www.youtube.com/watch?v=KOh6kKrQioE
Should get you on your way. I recommend checking out FatCat, 4AD (through the past twenty years or so), and Factory Records (now defunct) for a more dark sound in the vein of the XX.
[EDIT] I'll recommend too, pay attention to Pitchfork. They get a lot of flack but they're always reviewing and recommending relatively unheard of bands. Sure they can have some awful reviews and you don't have to go by everything they say (some of their 6's are great, some of their 9's are terrible), but they've exposed me to a lot of new music. To a lesser extent, Stereogum and Drowned in Sound are also breaking lots of artists.