Quality links to your store are still an important ranking factor and something you should focus on as part of your strategy. Shopify recently published a useful blog post on 'Increasing your page rank by getting links to your store' which covers some great methods to develop those links.
After years of working with businesses on developing their ecommerce strategies I only have one real tip regarding links.
DON'T BUY CHEAP LINKS TO YOUR STORE!!
I've seen it backfire so many times and has often lead to stores being given penalties and even removed from the Google index entirely. So don't do it.... ever!