I'm on DSL and there was a bit of a delay in loading but it wasn't too bad. That said, people using "lite" services or... wait for it... dial up would face a pretty long wait. In such a competitive business where there's another (possibly faster loading) photography site around the corner, it may be beneficial to strip a few of the photos from the main page to improve load time.
One suggestion I have is to use that feature in blogs where visitors can only see the beginning portion of a post on the main page then have to click a "more..." link to view the rest of the entry. If you just post one sample picture before the cut people can click to expand only the entries they're interested in. I'd imagine this approach would cut down your load time significantly. And, since visitors would still see one sample picture for each post on the homepage, they'd know exactly what to expect once the full entry loads, which isn't a bad thing.
Also, I just wanted to to echo Wazza's comments: you've got some great pictures there.
Hope that helps.