Google’s 2026 holiday guide for retail advertisers opens by welcoming readers to “the first AI-powered holiday season,” a framing that sits against Google’s own trading record: the company deployed agentic checkout and conversational shopping across Search and the Gemini app for the 2025 season and published a separate holiday guide in November of that year. The numbers appear impressive at first glance, but PPC Land’s analysis unpacks some inconsistencies.
Etsy is the headline case. Per the guide’s case study, the marketplace used AI Max to interpret shopper intent and automatically tailor ad headlines, paired that with shoppable YouTube videos, and drove a 36% year-over-year increase in gross merchandise sales across the 2025 holiday season, partially attributed to AI Max, alongside a 21% rise in new buyer acquisition. None of the guide’s three case studies carries a measurement window, a control condition or a statement of incrementality method.
Google-commissioned Ipsos work among 8,237 U.S. consumers puts AI usage at 61% of shoppers during the 2025 holiday season. Of those users, 94% found the tools valuable in their shopping. The guide claims that AI Overviews has passed 2.5 billion monthly users, but that is footnoted to an Ipsos panel of 1,275 U.S. consumers, creating a bit of unusual confusion from a platform that has solid metrics on nearly every person who’s ever touched a browser.
The 15% conversions lift the guide attaches to AI Max comes from a February 27 to March 12, 2026 window restricted to non-retail advertisers. Independent measurement runs the other way. Smarter Ecommerce analysis of more than 250 retail campaigns found conversions delivered at roughly 35% lower return on ad spend than traditional match types in November 2025, and Lunio found retail AI Max search campaigns carry 72% more invalid traffic than the platform average.
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