I've thought about building something like this for a while. There is definitely a need.

I've found a huge problem with products is that their quality changes over time. So, a product may be named the same but the SKU changes or the products from a couple of years back were much better made for whatever reason while the company has gutted them and continues to sell on reputation. I've wondered if there's a way to track product changes (user reported maybe?) between revisions of products on a wide scale. Can you convert the "years owned" to a purchase date somewhere? Are you tracking SKUs?

How will you handle fake reviews?