On an e-commerce site with no username/login to persist cart data, would it be better to use the PHP $_SESSION variable or a browser cookie to persist items in the shopping cart
I would store it in a SESSION. My wish list is rather long, and I am afraid that it will not fit in the 4K storage that a COOKIE may occupy. It forces you set the session time out to a longer period.
note: there are some countries (like the Netherlands, where I am) that have very strict policies about cookies, and you may be forced by legislation to use Sessions.