I use Dropbox and WriteRoom for everything and this fits in those really well. If Im compiling thoughts or lists in WriteRoom and dont want to switch apps, I can add or modify something in the todo.txt file easiern a tweet and it corresponds beautifully when checking the todo.txt app later.
Great for easing into GTD as well.
This app is a great solution, I dont feel like my priorities are siloed in a little niche on my phone. Open can be elegant.
Will Pierce about Todo.txt Touch