Hemos elegido el TextMate, estas son sus características:

• Ability to Search and Replace in a Project
• Auto-Indent for Common Actions Like Pasting Text
• Auto-Pairing of Brackets and Other Characters
• Clipboard History
• Column Selections and Column Typing
• Completion of Words from Current Document
• CSS-like Selectors to Pinpoint the Scope of Actions and Settings
• Declarative Language Grammars for Graceful Mixing and Hacking
• Dynamic Outline for Working With Multiple Files
• Expand Trigger Words to Code Blocks With Tab-able Placeholders
• File Tabs when Working With Projects
• Foldable Code Blocks
• Function Pop-up for Quick Overview and Navigation
• Plug-able Through Your Favorite Scripting Language
• Recordable Macros With No Programming Required
• Regular Expression Search and Replace (grep)
• Run Shell Commands from Within a Document
• Support for Darcs, Perforce, SVK, and Subversion
• Support for More Than 50 Languages
• Switch Between Files in Projects With a Minimum of Key Strokes
• Themable Syntax Highlight Colors
• Visual Bookmarks to Jump Between Places in a File
• Works As External Editor for (s)ftp Programs
• Works Together With Xcode and Can Build Xcode Projects

Suena bien, ¿verdad?

Y un par de enlaces sobre el editor:

• La web de TextMate
• En el artículo "Using Ruby on Rails for Web Development", dicen: "
  Finally, we recommend that you download and install the 30-day
  trial of TextMate to use
  throughout this tutorial. It's a popular editor for Rails
  developers on Mac OS X."