I posted before on How to Install Windows Vista or Windows 7 from USB Flash Drive which uses manual command line method to transfer your CD/DVD installs onto the bootable USB stick. I just used that other day to build bootable USB stick with Windows 7 RTM and it works great.

However, I just found about free WinToFlash utility which automates that process. So, if you are in hurry to build that bootable USB stick with Windows install it might come handy: http://wintoflash.com/home/en/

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