Luckily, the two choices aren't mutually exclusive. You can get her one that's small and stylish that also takes very nice photos.
Take a look at the following cameras as examples:
Konica Minolta Dimage Xg
Kyocera Finecam SL400R
Canon PowerShot SD10
How much should you spend?
Ultimately, I think a more important issue is how much you want to spend on a camera for a teenager. If she's shown an interest in photography and you think she'll want to work with the images, you might consider paying a bit more for a higher-resolution model, such as the 5-megapixel
Canon PowerShot SD20. If all she wants to do is take snapshots, then a 3-megapixel model should suffice.
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