Sorry for the shouting...
Lots of Django Shopping Carts...
but not many platforms for commerce..
That was my essential itch when Collector City was concieved...
In a nutshell:
Multitenant (multiple marketplaces with multiple shops in a single instance of software)
SAAS Ability to Run the entire platform as a service
Payments I have four payment processors, and (hopefully) made it easy to add more..(paypal, google, manual, braintree, subscriptions )
Designers Shops are fully customizable templates (I use jinja2 for the shop's templating engine)
Search It's hard :(, and I think we have a good integration
Security I've spent a lot of time and effort here, but you can never have enough eye balls on this..
Auctions A million shopping carts, slim pickings in the auction side... a lack of open source projects in general, Django is no different