Umbraco 4 features a live editing environment that sets new standards for working with web content in context. Instead of switching between an editor and preview on your website, the level of true what-you-see-is-what-you-get is finally reached
Imagine that while browsing your website, editable areas gets marked as you hover them with your mouse. That clicking the area immediately reveals the same rock solid editor as you know from the traditional umbraco back office, but this time at the exact same place and size of the content you're editing. That this isn't limited to editing visible items, but that hidden items like meta data and page configuration specific items are editable as well. All adjusted according to the permissions granted to you.
If you're imagination hasn't left you, you're probably smiling and excited right now. If not, you'll be when the final version of Umbraco 4 reaches your website. It's stunning. It's true live editing, not just a gimmick. Like any other umbraco innovation.