Theres already an improved desktop UI in the dev preview. Works the same as usual for the most part. And you access the new Start Screen (metro) to get to programs the same way as you would by clicking on the Start button on the desktop.
Programs are now alphabetically displayed full screen using the metro UI – it's a lot easier to find stuff. No more hunting through folders in the "All Programs" start menu thats inside some tiny area that you constantly have to scroll. So no, metro isn't a waste of time even for work, it also makes stuff quicker. You dont even have top open a search box, just start typing and it will display results.