Love the simplicity of your design, you certainly have an eye for design looking at your portfolio (i'm also a big fan of fancybox

, nice to see someone else using it).
Things I would change, I understand why you have built the site all on the index, to get the effects, however it seems strange seeing it on an actual site. I've seen it before with jqtouch and iui but never on a full website. I agree with other posters that you maybe best fragmenting your pages for usability, this is just my personal opinion though.
Also I noticed you have done a small bit of responsive design on the site, but unsure why you have neglected to follow it through on the smaller screens. If you maximise your site, you get nice big icons, however if you start to shrink the window, you get the normal site, and thats it. It would be good for people viewing your site on tablets and phones to see a more optimised version. Google fluid grids for more info about this.
However the above is only what I would do, keep doing what you are doing as you seem to be doing well.