Nothing! I'm Italian and my thought aren't explained in the right manner when I try to make my (poor) english comprehensible to other people! :) Well, Kelly has a really wide range of things she can do: enormous vocal talent. Here, in RU-vid, I've found a lot of interesting thing, but too "sour" to be compared with someone like Kelly or others. "Since you've been gone" is a bit far from the ability and the vocal quality of Mia: she can do, and better, many different thing.
no don't murder unique tush's comment, i totally agree, i love love love kelly, but this isn't her best performance. this sond should be done a lot slower.