Matt Cutts says 404 unavailable products on the 'average' ecommerce site.

[Coraltoes77]

If you're an ecommerce site owner, will you be changing how you deal with unavailable products as a result of the recent video from Matt Cutts? Will you be moving over to a 404 instead of leaving the pages live still?

For us, as more products were becoming unavailable, I had started to worry about the impact of this on the website (bad user experience, Panda issues from bounce rates, etc.).

But, having spoken to other website owners, some say it's better to leave the unavailable product pages there as this offers more value (it ranks well so attracts traffic, links to those pages, it allows you to get the product back up quickly if it unexpectedly becomes available, etc.).

I guess there's many solutions, for example, using ItemAvailability schema, that might be better than a 404 (custom or not).  But then, if it's showing as unavailable on the SERPS, will anyone bother clicking on it anyway...?

Would be interested in your thoughts.

[Kingof5]

I won't be changing what we do with out of stock items. A 404 is a bad user experience. One of our sites sells tons of products that all come in a variety of colors. 5 of them are core colors that we always have, the rest come and go. So when one of the colors that comes and goes runs out of stock and the page 404s, we 301 it to a core color that shouldn't go out of stock. And for the rare times that we're out of stock on a core color, we use out of stock messaging on the page instead of letting it 404. I was surprised he didn't mention redirects in the video.

[MikeRoberts]

Personally I prefer leaving the unavailable products (ones that will never come back) up & accessible for a set amount of time, placing a notice & link on the page to the most relevant available product or related category page, placing a canonical on the unavailable product page to that related product/category page and then after a few months redirecting the unavailable product to the related page.

[AlanMosley]

I see it like this, its a bad experience to find that a item is out of stock, the 404 will remove you from the index.
A site where you have a lot of products is probably not be ranking well for ever product page anyhow, I would be getting category pages to rank. and not be worried about a few lowly product pages