Hi Mark and Ori,
This looks like a great sample/project. I watched the video of your session and was eager to get my hands on it.
I'd encourage you to do as much work as you can on the true e-commerce aspects of the application. Too many samples are really just catalogue/brochure sites that add items to a shopping cart and go no further.
Trouble is, the site developer/owner is then abandoned to build discounts, coupons, "two-for-one" offers, shipping costs, credit cards, and parcel tracking components into the base app. As you know, that's a lot of work that seems to be done over and over again and not necessarily well.
The use of best security practices will be important in your sample as well.
Looking forward to your first CTP!