You have seen the screenshots but at the recently concluded Max 2007 conference, Adobe gave a live video demo of some prominent features in Photoshop Express, the much awaited online image editor.
Like the live preview feature in Microsoft Office 2007, you can hover the mouse over various thumbnail images in Photoshop Express to see how that effect will look when applied to the current image - it's efficient and lightning fast.
CNET has the recording of the Adobe Photo Express demo which is embedded above. It's still not known if the online Photoshop editor can deal with layered PSD graphics.
Related: Edit Photos Online for Free