This article could also be in "School" or "Programming", but since my tests are made on #Instantbird using Instantbot...
I finally got it working on the last 150 days on #Instantbird, and here are the early results:

The bigger the node is, the more this person has connections with other people (click to enlarge in SVG)

Of course the results are experimental, a lot of other stuff is coming soon on this project.
To generate this graph I use Gephi, IRCParser exports with GDF format, but I plan to export to GraphML, so that we are compatible with more Software. IRCParser will be eventually released as a Free Software when it's ready , and of course will be usable for various log formats, and various output data.