Some thoughts.
Make the homepage a permanent page, rather than a blog page that updates. Use that to showcase your best work, you really want people to come to the site and immediately be wowed by the photos.
With that, you could then add a box below the main eye-catching content showing your latest work with a selection of the better photos.
Change the "See our latest work!" tab to something simpler, like just "recent work", or "showcase".
Not a fan of the font used in the navigation tabs, a sans-serif font would probably look better. Font throughout the rest of the site looks great though.
slightly transparent navigation is nice, but could do with being a bit more opaque.
Make the search bar longer, and give the button some styling so it fits the rest of the site.
Work on your marketing a lot, you've got FB buttons in your posts, but they're hidden away at the bottom where people won't find them. Consider adding a button right near the top, creating a Facebook page for the business and adding a like box for the page on your site.
http://developers.facebook.com/docs/reference/plugins/like-box/Give your site a major SEO boost by enabling pretty URL's. (it's under Permalinks in the Settings section of the admin panel).
Your home button goes to "www.photographyby.com" but the site is at photographyby.co, keep it to one thing, and don't change it. www is probably best, so change general site settings to reflect that.
Just my first thoughts, will probably have more later.