Pacman 2.6.1 is mostly a bugfix release with one nice add-on: Aurelien Foret has submitted his first patch for http support. No proxies or resumes yet, but "http://" urls work in pacman.conf now.
Also note that the default ABS directory has been changed from /usr/abs to /var/abs. This option is configurable in /etc/abs/abs.conf.