I may be biased but I feel that #GeoEdChat may be the best innovation of 2013 (well maybe so far!).
Based upon the large range of twitter chats that already occur, a group got together, led by Dan @RavenEllison to fill the gap in Geography chats.
A website has been set up (http://geoedchat.com/) and the chats will be hosted in a different timezone/region each week so all parts of the world gain equal access.
A moderator takes control for each week and sets a poll of topics they are interested in. A week before the chat they will post a blog on the website with their thinkpiece to stimulate the chat when it occurs.
The first chat is happening 8pm London time February 6th and will discuss how geography can be at the centre of your school. The thinkpiece for this is by David Rogers, who will be moderating the chat, and has just been posted online now for reading and discussion beforehand. Have a read and then vote in the polls for the upcoming chats.