Status: Active development.

Link: http://psi-im.org/

Pros: Active development, ability to alert users on other protocols as to the existence of IRC, support for multiple emoticon sets.

Cons: No extras such as can be found in Colloquy with the exception of emoticon sets.

Review: Actually quite a nifty IRC client, if you are willing to spend a little while setting it up. It's not as powerful as Colloquy or Linkinus, but it's not to be ignored. It's certainly lightweight and quick on it's toes, so by no means a flop.