100%....Most customers don't even understand https vs http. In the tech bubble, we definitely recognize things like that, but for normal people, they determine their trust by the look and brand name on the payment form.

This button is the first step for stripe to start being a trusted name by more skeptical e-customers.

I would trust Stripe, but only after seeing it verified as the owner of the SSL certificate of the website I'm using. There's way too much phishing going on for me to trust anything just shown in HTML branding..

Of course I realize that 'normal' people might trust anything, but it still won't make me trust it any more. So I'm not quite sure in what situation I would personally ever be able to use these nice Stripe button payments.

Surely that's a bad thing? It would be trivial to make an identical Javascript popup which harvested data rather than sending it off to Stripe. Yes, the current redirect-ad-infinitum workflow is reasonably trash, but this scares me a lot, and I'd personally not trust it.

I think the idea would be that this is in a https payment page of the client company who you would then choose to trust (or not) as implementing the payment frame correctly. Just like if they had their own payment solution essentially.

Besides how does a pop up make it more likely to be an iframe than just any old iframe?