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It is not available on my (free) account in either the app or the website. So no, everyone does not have access to it.

It's for paid users for now, not free. I have ChatGPT Pro and I can use the new model.

I am a free user and I have 4o. I think it is just a gradual roll out.

That sounds about right, it just seemed that everyone who replied above who had access to the new model were paid users.