Hi, I've picked "General' because I'm not sure where else to post this issue, could be tech. but applies to SEO too.
I don't really want to get into the discussion if urls with db ids in them are bad for SEO or not. I don't think they are really, but nobody likes them anymore so lets get rid of them.
Currently the only choices in PS for urls are urls with ids or 'static' friendly urls. By static here I mean urls that have for instance the categories / category / product name / etc. in them in such a way that when either of these names change, the shop's backlinks for this url break, which is not nice for SEO at all.
Another problem is name collision, when you want really short urls, but categories/products/brands have identical names, the urls break. Or even in cases where there are -many- product in a shop, names can collide.
In several shops I've solved this by not using the internal database id in the url, but another identifier, like the 'reference' or EAN13 for products and a 'reference number' for a categories to identify them so that when the name of the category or product change the specified category or product can still be found (by lookup in the dispatcher).
Example:
url: www.shop.com/white-gnocci-shorts/S332.112 Where the last part of the url is the products reference. Now, if I have to change the name of the product for whatever reason it won't be a problem because it will be looked up by the reference and backlinks never break.
I've chosen to use an identifier like 'reference' or EAN13 because I've been working in situations where name collision between categories/brands/products/cms pages are impossible to avoid.
In short what I mean to say is, I'd like (and need) 'nice urls' with a unique identifier other than the database id, like in the examples below:
Category urls:
shop.com/socks/blue-socks/C321
shop.com/socks/red-socks/C212
Product urls:
shop.com/my-nice-product/P32111
shop.com/my-other-nice-product/P43821
shop.com/my-first-product-with-a-changed-name/P32111
Ofcourse the identifiers need to be configurable in the SEO section of the shop... Maybe a SEO identifier field for each object?