I recently purchased this doll for my little sister. When I saw the cool commercial, I just knew I had to buy her one. Unfortunately, I think I was more excited about the doll then she was. She doesn't play with it that much and she threw Barbie's plastic cell phone in the trash, because in her words "it looked stupid".
This doll is about average Barbie height (11.5 inches). If you raise the microphone to her mouth she sings songs; if you raise the cell phone, she talks on the phone. As advertised, you can also plug in your mp3 and Babie will move her mouth to the vocals (NOTE: she doesn't sing the songs in her barbie voice).
I think this doll is a great idea. I wish I had one when I was a little kid. Unfortunately, they are a bit expensive, and some of today's kids aren't impressed. Someday this doll will be very collectible. Hopefully my little sister will stop throwing barbies accessories in the trash