As of now, the Product Reviews Update still requires a periodic refresh. Sites need to improve and wait for the refresh to see recovery.
Google published a new post about the Product Reviews Update & introduced two new best practices, but they are NOT being taken into account yet for rankings.
First new guideline:
1) Provide evidence such as visuals, audio, or other links of your own experience with the product, to support your expertise and reinforce the authenticity of your review.
Second new guideline:
2) Include links to multiple sellers to give the reader the option to purchase from their merchant of choice.
The December Product Reviews Update was core update-like for many sites (surging or dropping heavily).
Recovery:
Some sites that worked hard to improve after the April Product Reviews Update surged back in December.
Hard work can pay off, but just takes time...
Dueling Machine Learning Systems:
It was clear there were dueling machine learning systems at work... with broad core updates sometimes at odds with the PRU.
Dueling Machine Learning Systems (cont'd):
Some sites even reversed course from the Nov broad core update, which launched just a few weeks before the Dec PRU!
Dueling Machine Learning Systems (cont'd):
And others had a history of surging or dropping during Broad Core Updates and Product Reviews Updates.
So, will dueling machine learning systems keep battling? Listen to Google's John Mueller next...
With multiple machine learning systems at play, it would make sense for Google to bake the Product Reviews Update algorithm into its core ranking algorithm. Listen to Google's John Mueller by clicking the sound icon above.
Intent Shifts Prevalent
There were clear intent shifts in the search results during the rollout where Google was swapping review sites for e-commerce retailers and vice versa based on query type.
So, it's beyond just a page versus page comparison.
Looking to improve? Become the Wirecutter for your niche. You can't go wrong...
The Wirecutter Standard:
From thorough and balanced reviews to strong photos and video to transparency about their process, Wirecutter reviews are stellar.
Learn more about Glenn Gabe of GSQi.
Read Glenn's full post about the December Product Reviews Update.