When developing web applications, in the past the choice has been 800px
or 1024px
to fit within the monitor of the user. I\'ve been researching respon
980 is not the "defacto standard", you'll generally see most people targeting a size a little bit less than 1024px wide to account for browser chrome such as scrollbars, etc.
Usually people target between 960 and 990px wide. Often people use a grid system (like 960.gs) which is opinionated about what the default width should be.
Also note, just recently the most common screen size now averages quite a bit bigger than 1024px wide, ranking in at 1366px wide. See http://techcrunch.com/2012/04/11/move-over-1024x768-the-most-popular-screen-resolution-on-the-web-is-now-1366x768/