A lot of people in GNOME use a dedicated IRC application called XChat, but that Empathy lets you connect to IRC too! So I can show you how to do that in a few minutes ;D
Empathy is an application that GNOME 3.2 has by default:
1. Click on the button + to Add your account on IRC.
2. Click on Protocol and choose IRC.
You can set your nickname, it is not necessarily enter a password.
3. Click on Network and choose irc.gnome.org. If you can not see it, click on Add.
4. Go to te Server block and click Add, by default the port 6667 is activate, if you have troubles ask to the administrator because some institutes and universities avoid it.
5. Click Close.
* Then, you can click on Network and you can see irc.gnome.org in the list.
*Click on Select and set your user, in my case I will be yulys 
* Go to Empathy and click on the menu
Room > Join room
* You can put #gnome-women, #docs, #gnome-love or the channel you prefer.
I know and I would like using empathy for jabber and other connections but sadly it has neither pidgin-encryption nor otr-support.
It’s easier to have one application for chat and in my case that’s pidgin
Excellent tutorial, we need more material of this quality.
However, this belongs into the official GNOME Documentation/Wiki, not into a random blog post!
Thanks Jens, I am adding this information to the https://live.gnome.org/Empathy/Documentation page
I find that empathy is unusable right now for irc; it should be better when this mockup is implemented http://gitorious.org/gnome-design/gnome-design/blobs/master/mockups/empathy/conversation-view.png
Two more things:
1. You don’t need to add irc.gnome.org, it’s already there. It’s named GimpNet.
2. You need to mention that one needs to have telepathy-idle installed.
Yes, OTR is a useful feature for me too, and there is actually one curious bug with IRC in empathy that made me go back to xchat. It stops keeping up with new messages in a rather random fashion, making you manually scroll back to the most recent messages far too often, especially in busy channels.