You can now update your QLRanks elo from Quake Live using the QLM bot, if you do not want to join #QLRanks and use !update on IRC or if the [QLRANKS] irc bot is offline.

Step 1: Add the player "QLM" to your QL friends list. The friend request will be accepted automatically.

Step 2: Send the message .update or .update PlayerName to QLM on Quake Live. You can use the chat box on the QL site or the console, or you can bind to a key. (The bind would be: bind x tell_buddy QLM .update)

Auto updates:
The QLM bot can also update your Elo when the map changes or when you disconnect from a duel, CTF, CA, TDM, or FFA server. To use this, send the message .autoupdate on to the QLM bot.

Hopefully this is helpful.

Update (September 28, 2014): Re-enabled .update and .autoupdate on the QLM bot.

Update (July 13, 2013): One-click elo updating for QLPrism users. See screenshot above.

Update (June 19, 2013): QLM bot can now auto-update FFA games

Update (Apr 10, 2013): QLM bot can now update/auto-update CTF games and for auto-update should no longer double update on map change and disconnect