The new Modern(ex Metro) UI is a big Start menu(now called start screen). You go to it only when you login to your machine after restart, after a login from sleep/hibernate/lock if you have left it on the desktop , it stays there. Everything else is like or better than Win 7.
Also you only go to the start screen when you need to find or start an app. Yes , for some users it would suck to see the Start Screen after booting, would be nice if there was option to select which screen to show after boot.
Also , the Start Screen is very good tool for organizing Apps. You can create columns of apps (not automatically though) by type , use case or whatever order your heart desires. And i find the start screen better replacement of the desktop for placing my icons ( i dislike cluttered desktops as i see it more often than the Start Screen)