This is not the lamp I bought at IKEA this weekend, but it's nearly identical. (I can't find the actual lamp that we bought on the website.) This is the FOTO lamp, and it's 10" across at the bottom. Our "mystery lamp" is 15".
I liked the simple, cheerful shape and not too shiny, not too dull silver color.
The best part was the price: twenty bucks! It's no yellow tin lamp from CB2, of course, but it's still makes me very happy. Maybe one day when I need something fresh, I'll hit it with a coat of yellow (low-VOC) spray paint.