Mission Control,One of the major features Apple put in Mac OS X Lion.It is an Expose style representations of all your desktops and running application But Its main problem is that it has that dull looking Grey-Wallpaper in the background.Well,We’re lucky there’s work around to get rid of it :D Its a simple procedure.It just involves replacing some files in the root on OS X.
Lets begin ——>>
Step1 : Start your Mac if you already haven’t.
Step2 : Navigate to System/Library/Core Services
Step3 : Look for Dock.app and Right-click on it.
Step4 : Click on Show Package Contents and then on Resources.
Step5 : Look for defaultdesktop.png and back it up on your desktop
Step6 : Now Make a Wallapaper or just google it [It should be 256×256] and name it defaultdesktop.png
NOTE : If you just back up and delete the file you will have the default Lion wallpaper we all love as your Mission Control BG
Step7 : Drag and Drop your desired image in the Resouces area,It’ll ask you for your password;Enter it and press Authenticate.
Step8 : Close the Resouces windows and log off and log back in.
Step9 : Et Voila ! You have an all new Mission Control BG
Step10 : Enjoy
Video Demonstration here —>>>>>