I recently build a commerce iphone case shop, which mainly deal with iphone cases and pouches.
At first, I thoght for long time. I don't want to use a shopping cart such as OSCOMMERCE and ZEN CART.
Although they have SEO plugins and can build SEO friendly shopping cart. But these scripts doesn't write in good function and will increase the compressive stress of th server.
I thought for long time and at the end I choose the wordpress to build a shopping cart.
The advantages of using a wordpress as shopping cart:
1. you don't need to worry about SEO problems. Wordpress has large amount of advantages SEO plugins.
2. It has good structural frame, all scripts worked at hight effective level.
3.Large amount of themes. You don't need to design your self.
4.A plugin named eshop can help you build a shopping cart with wordpress.
5. Tags and archieve can help you get more contents.
6. You must own a small business. you can add or modify your products just writing blog articles.
7.Performance well when customers buying products. As a example you can have a look at this site SNIP