There are some good items on the road map, but still some very key items missing before I can use the MojoPortal webstore for most of my clients that need eCommerce.   Here's a short list, but I'd happy to give more detail / requirements, etc. if asked.

• *** Store Layout Options in the Admin area  (Most common request:  allow products/offers to layout in a more typical grid fashion with a thumbnail, title, price (discount price if relevant) and add to cart option).   Allow add to cart to be optional as you may want to force people to get the full product page to choose options or see more detail prior to adding to the cart.
• ** Add product attributes (Second most common request) ... I've seen this done where users can add as many product attributes as they want dynamically and decide on field type, such as drop down, text entry field, memo field, etc.)    My most common request is to capture up to 2 attributes that could be in a drop down (size and color for example), so if you needed something quicker and easier for now, maybe offer 2 or 3 fixed attribute options where admins could label the fields as they wished and be able to add values.  
• Product Attributes should have the ability for price mark-up   (i.e. size XXXL requires an additional $2 per each)
• Products to be treated as "attributes" or linked to products in offers.   Less requested and more advanced, but needed on larger sites - Similar to the above, this would allow inventory of blue, large shirts to be at a product level, but all shirts to be in one offer with a drop down of color/size determining which actual product would be ordered.   
• Product categories - common request and tightly related to store layout options ... simplistic option would be one level of categories, but ideal would be the ability to have multiple/unlimited levels of sub-categories.   Right now we try to handle this via multiple store instances on the same site, but that is bad for reporting and site management and adds a lot of unneccessary work
• Agree with Roadmap about integrating to 3rd party shipping and tax calculation solutions ... however, both seem to be a lower priority to layout and attribute options.   I also like other things listed on the roadmap, but feel they are a lower priority to get a higher number of people using webstore.
• There are hundreds of other little features that can continue to be added to make this a more viable eCommerce solution / shopping cart competitor, but a few of these basics would go a long way.