Think 15% is high, how does 20% sound ...
According to Sedo's most recent email regarding pricing I received this morning, and is also mentioned in the new price list on-line.
"When you list a domain for sale, that domain is automatically promoted across Sedo’s Domain Marketplace, including the SedoMLS Promotion Network, where eligible."
Emphasis mine - listings may now be automatically promoted, without any additional action of the seller, on SedoMLS potentially resulting a fee of 20%.
Bottom line is some sellers, especially those with "Make Offer" listings, though it could potentially affect some "Fixed Price" listings too, could end up paying double what they are now ... 20% is a steep premium to sell a domain.
On a related note, while SedoMLS in theory should result in more exposure, it could also be abused by Sedo ... ie. a person finds a domain the usual way (type-in domain / search on Sedo's website) and then during the sale process, the buyer is routed through SedoMLS to boost the rate to 20%.
Imho, the end-game appears to be that Sedo is seeking to double its price to 20% in a back-handed way ... they likely figure if many people accept 15%, they'll tolerate 20%. Especially since some sales venues charge even more, so it makes sense for Sedo to try pushing the rate to 20% across the board. Whether buyers and sellers will pay that is debatable ... many people will be motivated to list elsewhere and/or cut out Sedo during the final sales process resulting in Sedo getting zero.
Ron