Microsoft shows off Windows 8.1- Video

Here’s a list of the major changes in Windows 8.1. you’ll notice the Start button is back on the desktop.

Lockscreen is a cloud-powered photo frame. Brings pictures from your PC and phone through SkyDrive.
New tiles sizes: Large and small.
Improved all apps screen. Swipe up from the Start screen to get all apps.
All apps can be sorted by most used, by name, by date installed, or category.
Press and hold to pin to Start
Press and hold like windows Phone to manage apps on your Start screen
New personalization that can quickly be accessed by from the Settings charm
New colors for background and accent colors.
New motion accents for the background. Hard to explain, by attention during the 1:53 mark.
Desktop backgrounds can now be used on Start.
New search feature powered by Bing that curates searches from both the web and PC.
Better multi-tasking
Up to four Windows 8 apps on one screen each with adjustable sizes for Snap mode