With the advent of the new "Show this page as the front page" option, calling get_permalink on that page still returns the full permalink.
For instance, if you choose a page called "Home" as your home page, get_page_link (with pretty permalinks enabled) returns "/home/". Shouldn't it return the siteurl instead?
The only issue I've encountered in doing this is when you try to get that page's attachment(s) permalinks, it returns the wrong permalink. That page's attachment permalinks become "/attachment/" (wrong->404) instead of "/home/attachment/" (correct). get_attachment_link calls get_permalink on its parent to get the root of the link.
Should get_permalink return the siteurl or the full permalink for that page?