Twitter has limitations with creating custom profiles… backgrounds are difficult to upload and depending on your screen size, they’ll always look different. So, why not take advantage of this twitter craziness and throw in something for the user/viewer to find…?
Here you can see the profile on a regular 1280w screen. Then, when you open the page on a screen with a bigger width, you get a nice little easter egg that includes a 50% off coupon for all products.
1280 px Screen
Twitter Easter Egg
1650px Screen
Popularity: 7% [?]
That would be especially valuable if you saw analytics data suggesting people with bigger resolutions (eg wealthier people with bigger screens) buying more, for example, or converting better.
Sure… It’s definitely possible to track screen resolutions… whether or not someone would actually do it is another issue…