I recently accidentally clicked the "minus" button on the "Login Items" screen under preferences, and even though I realized the mistake instantly, I had no way of getting the deleted line back. What make it worse, is that I have no idea what the line was that I deleted. "Undo" obviously didn't work, and because OS X applies changes as you make them, I couldn't simply hit "Cancel" like you can in Windows. This made me realize that Apple design approach to such dialogs, and the decision to apply changes as you go without providing OK or Cancel buttons is a fairly significant usability flaw. It's ironic that they go to extreme safety measures when it comes to file deletions in Finder (requiring a key combination; plus it goes to trash anyway after that), yes it many other areas of the operating system, they've made it way too easy to accidentally delete something. I'm just wondering if anyone has had the same thought? I pretty much bought my Mac solely for the supposed better use experience, but Apple have me doubting that the user interface is really that much better than Windows (specially now that Windows 7's taken advantage of a lot of OS X features).