eBay has lost ground with merchants but I find myself buying more from eBay and less from Amazon.
You have to read between the lines of this survey. The fact that fewer Amazon sellers are also selling on Ebay does not mean that Ebay is losing ground. It could just be the case that merchants are finding it better to not split their sales between the two. Some could be exclusively on Ebay and others exclusively on Amazon. We don't really get enough information here to say anything about Ebay.