Good contribution, and it reminds me of something I have been wanting to talk about.
The most noticeable difference is the colors. In the first pic, the cardigan color is too close to your skin, and the chucks are terrible. The plaid shirt also doesn't work with the rest, color layering wise. The whole thing looks boy-ish.
I think the lesson here is not so much 'buy quality clothing' as it is: know what colors and patterns work for you, and know how to layer them.
You can probably do a lot better for the same amount of money.
EDIT:
Excuse photoshop skills, but here is a very quick illustration of what I'm saying
Warning: Spoiler! (Click to show)
Edited by dibango - 12/22/11 at 10:24pm