Well this KB is new to me, but worth pointing out anyway especially if you have a solid colour as your desktop background.

The Welcome screen may be displayed for 30 seconds during the logon process after you set a solid color as the desktop background in Windows 7 or in Windows Server 2008 R2

Applicable to Windows server 2008 R2 as well.

Of course solid coloured backgrounds are boring so go get yourself a cool Windows 7 theme or background image.

For more information on speeding up your computer try the following.

Rob

Originally spotted on Softpedia