Why geeks prefer plain text
According to the Life Hacks research done by Danny O'Brien, alpha geeks prefer using plain text files to track their to-do lists. In a computing era when beautiful GUI applications will perform innumerable activities to keep track of you and your data, why would anybody still poke at plain text files, especially on the utilitarian command line of all things?
Geeks don't want feature-bloated programs performing innumerable activities to their data. They want to pick and choose what they write down - or rather, type in - how they manipulate it, what has access to it, and when something gets changed. They also want to be able to see the trees for the forest, so to speak, without the GUI getting in the way of their work.
Why use a plain text file when there are dozens, if not hundreds, of "Todo list" programs available for nearly every computing platform imaginable? Why not take advantage of applications that keep track of task completion dates and task priority? Well, there are some good reasons to forgo the more advanced applications in favor of simple text files.
It's easy to try to do too much sometimes. Most "todo" programs are too complicated for the simple task that they serve. It's mindlessly simple to click on a check box to mark a task as complete, but viewing all of your pending tasks at once regardless of category or priority can sometimes require significant hoop-jumping. A simple text file or a series of text files representing categories is neither more complicated nor less complicated than the average todo application.
Text files work on all computers in pretty much all text editors and word processors. If something ever goes wrong with your computer, you can just take those same text files to any other computer you can get your hands on and still use them (just make sure you have a backup copy to use).
 Getting Things Done
The GTD concept of action lists rejects the idea of having dated or prioritized todos. Pending actions are organized by context more than anything else. To quote GTD, "I know this is heresy to traditional time-management training, which has almost universally taught that the 'daily to-do list' is key. But such lists don't work..."
Your text files are structured however you like them to be -- more to the point, they're structured however you need them to be. You don't have to adapt the way you think about your life in order to fit into someone else's concept of how it should be organized.
This is a concept that many people have a hard time understanding at first, but the simpler your data storage system is, the more powerful it can be. Text editors come in all shapes and sizes and flavors. Some are pretty simple like Windows NotePad or OS X's TextEdit. Others are full-fledged computing platforms in and of themselves like vi or Emacs. Those familiar with these advanced editors or with programming and scripting languages, can manipulate their text files to be anything they want. You want those text files to sync up with your Palm? No problem. Want your action lists uploaded regularly to a personal website and translated into easily readable webpages in the process? Easy. Want to print them out in a booklet format that you can fold up and carry in your pocket? That's what Wikipedia:PostScript is for.
Plain old text is nearly universal in the computing world (language barriers notwithstanding -- there is a plain text equivalent for every language). Whatever you want to do with your next action lists, you can do it if they're stored as text.
If you're using a UNIX-like operating system—such as OS X—you have at your disposal hundreds of individual and powerful tools designed to do sundry things to plain text files. Using command line pipes, you can instantly create your own complex programs created from these small utilities. GUI tools such as QuickSilver and GeekTool transform playing with plain text into an even more powerful activity.
The many distractions of modern desktop computing begin to fade into the background, allowing what really matters to come into clear focus -- Getting Things Done, to coin a phrase. ;)
Allin Cottrell argues convincingly for text editors versus word processors in the mildly titled Word Processors: Stupid and Inefficient. Just think to yourself: would you rather process words or edit text?