CD/DVD writing requires some more low level programming that is not something I am well not versed in. There are controls out there to do this sort of thing, but this is a small project that I did more so for fun than anything else, and I already dropped some bucks on a compression/archiving control as well as a few other things.
USB drives can cause problems, but in most cases, removing the drive properly will allow any writing to finish and corruption will not happen. Yes, it can, but as of Windows 7, plugging in and removing devices like a flash drive is even easier for the most novice of users. You can pick up 4 GB USB drives for $20 these days. Seems silly to me to archive data on CD or DVD and wait for the slow writing and possible issues with scratches, etc.
Edit: Here's an 8GB drive for $22.95:
http://www.bestbuy.ca/catalog/prodde...12&catid=20244