If you like IRC, you will like Chatterous.
It is like IRC where you can get msgs by SMS/IM/email/etc
It is like IRC where you can get msgs by SMS/IM/email/etc
So in other words it's not like IRC at all.
Additionally people have used an assortment of clients to receive messages including local apps, web based, etc.
It isn't about how you receive the message, its the structure of how people are organized to chat.