For anybody who's interested, I've just made a PKGBUILD to build SFML from the latest svn revision. It's available in the AUR here:
http://aur.archlinux.org/packages.php?ID=22731.
I will also be making PKGBUILDs for csfml and dsfml, they should be ready in a couple hours; and when SFML 1.4 is officially released, I'll also make PKGBUILDs for that.
Edit: The CSFML PKGBUILD is now available here:
http://aur.archlinux.org/packages.php?ID=22733. I can't figure out how to upload the three patches I made for it, but those bugs should be fixed relatively quickly and when they are, I'll update the pkgbuild. If anybody is interested, I can tar up the patches and put them on sendfile or megaupload or something.
Edit 2: The CSFML PKGBUILD has been changed so that it doesn't require the patches anymore.