Windows 7 is an awesome OS which supports all kind of Desktop effects;

New and changed features:

Handwriting Recognition;

Virtual Hard Disks;

Multi Core Processors;

Improved Boot Performance;

Direct Access and Kernel(Computing) Improvements;

Improved media features, the XPS Essentials Pack and Windows PowerShell;

This above picture shown is the Windows 7's taskbar and it has many effects;

Aero Snap;

Aero Shake;

Aero Glass;

Aero Peek;

Aero Transperancy;

And Windows 7 has fast processing capability compared to XP and Vista..

      Compared to the task bars of Xp and Windows 7  7's task bar is nice and easy to enhance;

XP Taskbar

In the Xp taskbar there are no special features which is enabled in windows 7; 

In 7's taskbar u can directly access to windows explorer by clicking the Windows explorer icon shown in the above picture;