Couple of fairly simple things they could do to at least help somewhat:
* Put reviews for current listing at the top of the reviews (currently default sort seems to be a vague "Top reviews", but can be changed to "most recent" which presumably accomplishes this. Vast majority never change defaults though)
* Clearly mark any review that is for a previous version of the listing, and provide a link to view the listing at time of review (so can easily see if it was a completely different product or a simple typo correction etc.)
* Perhaps make history of listing visible, so customers can see when and how the listing has changed
* Put reviews for current listing at the top of the reviews (currently default sort seems to be a vague "Top reviews", but can be changed to "most recent" which presumably accomplishes this. Vast majority never change defaults though)
* Clearly mark any review that is for a previous version of the listing, and provide a link to view the listing at time of review (so can easily see if it was a completely different product or a simple typo correction etc.)
* Perhaps make history of listing visible, so customers can see when and how the listing has changed