As obvious as that seems (after all, how can a gift recipient review a gift until it's actually opened?), there may be a few more subtleties in when retailers can expect reviews—and what type of reviews they can expect.
In particular, the company—which specifically tracked perfume purchases—said product reviews reached an all-time high in August, then dropped off until October, which is when customers wrote reviews of products they bought over the summer. Then as customers start in on their holiday buying, review writing drops off again until January.
That lag probably varies from one product category to another. The fragrance reviews that DooYoo tracked may have a much longer lead time than electronics, where customers often report on purchases with weeks or even days, at least in the U.S.
That leads to what you should expect from post-Christmas reviews. The fastest reactions are likely to come from the unhappiest customers—the toy that falls apart coming out of the box, the big-screen TV that won't connect or looks awful, the piece of apparel recommended by an associate that sends a teenager storming off in disgust. (Even on a busy Christmas day, there's always time to write a negative review with a howling three-year-old—or a sulking 15-year-old—in the background.)
Those worst-case scenarios are the first reviews that potential customers will see immediately after the holidays. A few days later, the more positive reviews will begin to trickle in, with the bulk of reviews showing up weeks after the gifts are actually opened, once holiday activity is done.
Just keep that in mind before making any plans to start mining your customer reviews (or those of your competitors) for insight into how customers like what they get this year. It may be a fast-track priority for you, but customers will do it on their own schedule—bad reviews first.