Colbie isn't a new artist....did you sleep through 2007?
Oh yeah, there's lots of others like Demi, Miranda, Kerli, Ting Tings, the aforementioned Francesca Battestelli, what about Lola? (Eiza Gonzalez) Is she new?
I can't put Lady GaGa because I just didn't like her song enough to put into this discussion. For me it's not the best, but it's by no means the worst.
And please 3 British people have mentioned Leona Lewis She won the X Factor in 2006, her first number one in December '06. Bleeding Love & Spirit both released in 2007. For US people it's okay because she's just out there