Dan McGee wrote:

We now regularly poll all official mirrors and gather statistics such as syncing delay, check duration, availability, and error conditions. This information is available on the [mirror status page][1]. Please consult the page for more details on what is collected, how often it runs, and how it works.

In addition, you can now [update your mirrorlist][2] and choose to have it automatically sorted using the up-to-date mirror status information.

[1]: http://www.archlinux.org/mirrors/status/

[2]: http://www.archlinux.org/mirrorlist/

URL: http://www.archlinux.org/news/mirror-status-and-custom-mirror-lists/