What size should web image be?

With the introduction of the "netbooks" and smart phones, I was curious to revisit the most common screen resolutions currently being recorded by web browsers and those data mining groups that do such things. One report I found lists 36% of surfers are using 1024x768 in January 2009, down a bit from 2008. Where is the move? To higher resolutions. The report only lists resolutions higher than 1024x768 and that percentage is 57%. But are we possibly seeing a move back to smaller screens? Do the data mining groups account for web browsing on smart phones? I know that I look at images on an iPhone, Macbook Pro, and a 24" Apple Cinema display. I have looked at the netbooks and can't say that they catch my fancy at the present time. A quick look at one of the HP netbooks (N270) shows it sporting a 1024x576 screen resolution. Will netbooks find a strong foothold in the marketplace? Another consideration for how large of an image to post to the web is how much of an image do you want your audience to view. I personally always want the entire image showing with no zoom effect. Why? I take great care on the entire composition of the image and want the image always viewed in its entirety. To me, posting a larger than 1024 image on the web would be like Ansel Adams only allowing you to view one of his prints from a distance of 6" away. There is a proper viewing distance for all images and one should consider that even for web presentations. Now I do understand that some browsers can re-size the image to fit the window, but I really don't want to rely on that effect 100% of the time. So at the present time I have chosen to post images with a long side of 1000 pixels with some modifications for portrait orientation. To me that hits the sweet spot of fitting nearly every screen resolution out there (93%)and presenting the image in its entirety to the viewer. So that is my take on proper image size in June 2009. I hope to revisit the issue as time passes to see where screen resolutions may go into the future.