Jess kindly introduced this great chat client to us, and I think it has great potential. It is designed to be a sort of online roleplay medium, and that is amazing, but it is also a stable chat client. This is important, I think, because MSN is notoriously unstable and becoming more so.
On MSN for a second, it has reached the point that it is kicking users off almost constantly. I don't know about others, but it has been sending me tracking cookies and viruses. A messenger client that is unstable and possibly infectious can be a really bad deal...
IMC, on the other hand, may not have as many of the bells and whistles that MSN has but it makes up for that (in my opinion) with user friendliness and it's own tools that MSN does not have. Each chatter can have multiple "handles" or display names that they can switch between seamlessly. Each of these 'handles' can have it's own display pic, display name, and other customizable options.
I have already taken the liberty of starting a CWC private room for us to use.