IRC stands for Internet Relay Chat, a method for having large groups of people (or small groups) get together to chat online. The #wikispot channel is on the "freenode" IRC network. You can also access the chat room by clicking on the purple link to the right, or if you have java installed on your machine, you can click this link.
Other ways to access IRC include:
There are many other options, and if you already use a instant messenger program that connects to multiple services, you might check to see if it already supports IRC.
To connect, use:
Some wiki communities might have channels as well. One that is currently (2009) fairly active is the Davis Wiki IRC Channel. Feel free to stop in there and ask questions as well.