and technically the web is resolution independent - it should not matter what res a web site is viewed. Of course with today's heavily visual Web the way a web site looks is often important to the site owner/creator, so do try and find ways to make a layout that works in as many different resolutions as possible, (but its hard and if it don't go down to 800 very attractively then it's PROBABLY only a small percentage of your audience that will get a bad looking site - just make sure the site is still usable and it won't be a big sacrifice.
Obviously as always each project is different
