Dear Ina,
I do not know if you and your subscribers are aware of what is happening on eBay regarding shipping items by media mail. In the summer, I received an e-mail from eBay stating that eBay would be monitoring items that were listed for shipment using media rate and would disallow items that the USPS does not allow to be shipped using this method.
The next day, I received another e-mail from eBay informing me to disregard the previous e-mail as eBay would not be doing that at the present time. Apparently, that was not true.
I recently sold computer software and listed the item indicating that the item would be shipped by media mail. When I tried to print the shipping label on eBay, I was unable to select media mail. My only choices were first class and priority mail.
Below the option for media mail was the message: "Items in this category are not eligible for media mail." Next to this message was a clickable link that stated "Find out more" which brought you to the USPS website. Once there, it listed all of the items which can be shipped by media mail which included computer software.
I contacted eBay regarding this issue and was informed by the customer service agent that I could print out my label for media mail using the USPS website but not on eBay because eBay does not allow media shipping for the computer software category.
I then asked to speak to a supervisor who basically told me the same thing. He informed me that the only categories that eBay allows media shipping are Books and Magazines and Movies and DVDs and that had I listed my item in one of those categories I would have been able to select media mail.
I informed the supervisor that computer software can be shipped by media mail and asked that he refer my complaint to the proper department so that this can be corrected. I told him that if I list software in a book or movie category, people who search by category would not be able to find my item. I also told him that it now takes me more time to print my label at the USPS website because I now have to input the shipping information.
This took a lot of my time on the telephone trying to straighten this matter out. It is very frustrating that it is still not really resolved.
P.
Note from the Editor: There have been numerous reports of eBay allowing sellers to select USPS Media Mail as an option, collecting that rate from buyers, but not allowing sellers to select it when shipping. In July, an eBay moderator wrote, "there is a known issue that is causing Media Mail to be grayed out in some valid categories. We're working to resolve this. Thanks!" We're not aware of any update since. 
Longstanding eBay Media Mail Glitch Costs Sellers 
by: Marie