Wow… the timing is so bizarre I can barely believe it.
I stumbled across this post announcing support for OpenID on the Pixelsoup blog of JadedPixel, makers of Shopify. I’m not entirely convinced this even makes sense here, but whatever — it’s fascinating.
On the plus side, Shopify appeared to have disappeared off the face of the planet (in terms of stagnation) for a couple of months there, but their blog at least is alive and kicking. Certainly not for consumption by tomorrow’s audience, but potentially good for some e-commerce applications.
There is no WordPress of online shop software, which is slightly irritating. A great opportunity for a very high profile open source project: take OsCommerce and make it user-friendly and generally not-crappily-interfaced right out of the box! WordPress has done a few innovative feature things, but I reckon most of its success has been built on the grounds that it’s free software (heck, it wouldn’t exist if it couldn’t have forked B2) and the work they’ve poured into the interface.
I’m posting too much geeky stuff. Something non-geeky to come soon, I hope.

Hi — I realise your post is quite old now and this is a bit of shameless advertising on my part, but you might want to check out Shopalong if you have the opportunity. It’s essentially a re-write of osCommerce using the default osc db schema and many of the familiar objects but it’s PHP5 only, has a lot more OOP, uses Smarty to provide a fully-themeable UI, and is being designed specifically for developers who want to customise and extend the software without the usual headaches. The ‘Wordpress’ of online shop software? That’s the plan :)