I'm not sure that it's possible with the iPad.
The reason that the Surface's keyboard cover manages to be so thin is because the tablet is providing power & data connections.
A multitouch keyboard cover for the iPad is going to need Bluetooth for a data connection and a power source built in, because the iPad doesn't provide any power or data connection. That alone is going to add a considerable amount of thickness.
The iPad doesn't support trackpad or mouse inputs at all.
And the iPad doesn't have a built-in stand, which restricts the design of the cover to something which either has a stand built in, or requires the use of an external stand.
I think your best options are going to either be the Logitech
Solar Keyboard Folio, the
Ultrathin Keyboard Cover, or one of those "laptop" style cases such as the
Brydge.
It's possible that someone like Logitech will release a similar design to the Solar Keyboard Folio with a multitouch keyboard that will shave off a few millimetres, but it's never going to be as thin as the Surface keyboard cover.
While I think the Surface is a very ugly device with the number of exposed ports & connectors along the sides, and having the seam from the kickstand along the back, I do think the kickstand & cover are fantastic ideas.