Gadgehit.com writes: "One of the biggest issues that web designers face is how wide to make the readable area on a website, and how much white space to leave for advertising or aesthetic reasons. For years, the 1024×768 resolution has been the most popular resolution for consumers, which means the maximum absolute width a good web designer would use is 1024 pixels, but this resolution has now been usurped."
60°
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Ad 
620°
I think with the inclusion of the floaty share sidebars as well, 1366x768 seems like a more logical size or 1280x720. I still develop for 1024x768 resolutions though.