Piclen is great your the PC you use everyday, but when you want others to view your pictures fullscreen and dont (or can’t) get them to install picLens, then this blow up page is perfect. http://www.fullscreenflickr.com does the same thing, tho i think its just medium res pictures (but you can create links directly to your photo’s, even link to it from your flickr page).

So it has its use’s, and it many situations it better than piclen (but its many its not), Apples and Oranges.