Hate the new Facebook photo-viewing thing? Can’t deep-link to an image because of it? Take the &theater out of the URL and you’re back in business.
Another technique is when you are looking at the album thumbnails, open pictures into a new tab (either by right clicking or simply using the middle mouse button).
[Update] If you forgot to avoid the ‘theater’, simply refresh the page (press F5) and the photo will load on the old style page.