When you sell on eBay (or any other venue site), whether it is just to clear a few things out of the back bedroom, to make a little extra pocket money, or to build a successful, ongoing, online business, you are joining the world of sales and marketing. You are in business at least to some degree. How you operate in all related things will play a big part in your success.
Your eBay About Me page is one of the best things you can use to start promoting your business. And you should use if for that. If your approach to your business is to be a friend to each of your customers than you want to provide more information about you so your customers can feel they can get to know you. If you are operating as a more traditional business then you want your me page content to be more about what you offer and how your products and/or services will benefit the customer. Or you may be somewhere in between, making your me page the best of both worlds.
There is no universal right answer to this. There is only the right answer for YOUR approach to selling on eBay. I've never understood why but some people want to hide from their customers, which includes using a "posting ID" for the boards so people won't connect their comments here with their sales. I believe your board posts and your me page content should be an extension of who you are and how you conduct business.
If someone is being too rude, or otherwise unacceptable, on the boards to want people to connect them with their selling persona then perhaps they need to re-think their whole business strategy. More business can be generated from good behavior on the boards and great content in a me page than the opposite.
I can readily think of a dozen or more sellers whom I would purchase from at the drop of a hat because I feel comfortable knowing them from their posts and me page. Use these tools as they were designed and eBay becomes a powerful lead generation system.

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