OpenAI has experienced a significant surge in popularity for its ChatGPT service, with its user base doubling in size at an unprecedented rate. The recent introduction of an image generation feature has further boosted the AI assistant’s appeal. Today, CEO Sam Altman posted an update on X, revealing that the service has “added one million users in the last hour,” which he described as “biblical demand” for the image generation feature.

When the company announced the rollout of image generation in ChatGPT last week, the feature was initially intended to be available to all user tiers. However, due to the extremely high level of interest, access for free users has been restricted. The company is currently reporting “issues with new signups,” a status that has been in place for over a day.

While ChatGPT’s ability to generate original images has been a source of delight (and occasional horror) for users, the AI platform continues to face criticism from artists and creatives. Many of these individuals have had their work taken without permission, either as training material for the large-language model scraped from the internet or improperly taken and modified by ChatGPT users, without any credit or compensation. A notable example has been the numerous memes inspired by the animation style of Studio Ghibli. Altman is currently using one such image as his X profile photo; however, other users have used ChatGPT to apply the look of the studio’s films to violent or triggering content, raising fresh concerns about how creators can protect their work from misuse.