Online Shopping Carts? Is Satchmo any good?
MOdMac: Im in a similar situation, testing a move from magento to satchmo.  
Still in early testing but it does seem like a really solid cart which is much faster.The thing that really helps satchmo is the django base and the huge number of reusable apps available.In magento if you need forum or cms you need to add bridges to other packages all with their own auth and coding style.  With satchmo you can plug in one of the django forum apps apps let it share user registration with the rest of the site.The way that django has embraced reusable apps is the killer feature of the framework for me.