There is something about Ta-da List that works really well. Simple things like hitting return to save one to-do item and start a new one, tidying up of completed lists, and automatic ordering of recent lists. And above all else, speed. It is without question the fastest web app I use. Because the application is so focused, even full page reloads are faster in Ta-da than AJAX requests in some other web apps.
These are seemingly simple things, but they add up to an app that rivals any native (Mac or Windows) to-do list software. It makes me wonder how great a native app could be if someone put the same thought into user interface and simple workflow that Ta-da has. The advantage so-called Web 2.0 apps have over native apps is that they are inherently client/server based, but a native application could embrace the network in the same way and (maybe) provide a superior user experience. I’ve yet to see any apps that do this effectively, but it will have to happen if the desktop hopes to stay relevant for anything except tasks that benefit from large local storage (e.g. Photoshop and Final Cut Pro).
I use Ta-da List for everything now. Here’s a sample of recent lists: