Florence + the Machine
The album Lungs was pretty much my summer album of 2008. They really embody everything I like in a singer/band, they are quoted as to being "dark, robust and romantic" which I think fits them perfectly. Her vocal range is pretty insane, and every song is so emotionally powerful. Her newest album Ceremonials is great as well, if not better than the first.
I really found Lykke Li by accident, catching her music video for "I Follow Rivers" on television. Next thing I knew I had all her albums and had gone to one of her concerts! I think she brings something really unique to pop music, and if you can't sense a theme, I really appreciate witchy lady music. I love her use of unusual instrumentals, and her live songs are done in a fun and different way from the studio recordings.
Marina and the Diamonds
If I mention unique pop music I can't not bring up Marina, who has thankfully gotten more popular in the states with her newest album Electra Heart. I think I'll tend to prefer her first album The Family Jewels, just because it's a bit more darker, but they are both great. Every song is so lyrically interesting, she really is a very talented songwriter.
Kimbra is gaining popularity in America a bit thanks to Gotye, hopefully garnering more attention for her debut album Vows. I love her voice and I think her music is, for the most part, really upbeat and fun. Her live performances are great, and her use of looping vocals in them is pretty interesting.