Black Friday/Cyber Monday approaches! What will this year hold in the way of deliverability challenges?When I surveyed readers last year about their biggest mailbox provider challenges during Q4, Microsoft Outlook.com took the top spot. Microsoft was clearly the biggest source of inbox pain last holiday season. They are likely to continue leading the pack for sender deliverability headaches this year, but I predirect that Google’s Gmail is going to be a very close second.The 2026 Landscape: Gmail Enforcement and GPT V2Google has spent the past year steadily ramping up enforcement of its enhanced sender guidelines. And it isn’t just resulting...