there are still some poor sods out there with monitors that can't handle 1024..bless their hearts ('bless their hearts' is Southern for 'I'm about to say something bad about someone'..;). Some folks with better eyes than mine can actually see 1024x1200, which looks like legal documents to me..;)
as for different sizes, I'm sure it's just been rendered at different sizes, each saved as a seperate file. Found Digital Blasphemy over a year ago..hadn't been by in awhile.
Only thing to remember is to check your image when rendering in large sizes; last one I did looks fine at 800x600..but there's a little too much 'undeveloped property' at 1024x768..;) make sure there's some 'picture' everywhere..;) Another thing might be to keep the complicated stuff from the left hand side of the pic (you don't have anything to worry about here), because for most folks, that's where the icons are..and have enough contrast from their normal colors, so they don't get lost..all I can think of on short notice..;)

I wish I'd said that.. The Staircase Wit

anahl nathrak uth vas betude doth yel dyenvey..;)