In Linux, we do have a software called Terminator. In my Fedora's days, Terminal is my immediate replacement for Fedora default terminal. In Mac, we do have a software which behave like Terminator which is iTerm2.
Some of the iTerm2 features are:
- Split Panes
- Hotkey Window
- Mouseless Copy
- Paste History
- Instant Replay
- Full Screen
The best part of iTerm2 is you can configure your own shortcuts such as keyboard shortcut for split tab vertically, horizontally etc.
I personally think that for heavy terminal user should use iTerm2 as a direct replacement for default terminal :)
You can download it here http://code.google.com/p/iterm2/downloads/list