Conversation is a free and unassuming IRC client mainly aimed at users with little technological knowledge. The friendly interface and simple set up make for a good chat client to start out with.
Conversation lets you connect to multiple servers, as long as you have your user name and password. You can keep more than one conversation open at once and organize your contacts in groups. Like in other IRC clients, Conversation has simple drag and drop file transfer, emoticons and lets you customize your profile.
Conversation is supposedly aimed at newbies, so I was a bit surprised to find advanced features like XDCC or a customizable search box, which not all people will know how to handle.
Conversation is enjoyable to use, yet I wouldn't say it's more intuitive than MSN Messenger or iChat. Rather than going for it because it's aimed at beginners, I'd give it a try if you feel satisfied with the set of features.
An accessible IRC client, Conversation is a good alternative app for chatting.