It seems as if this isn't the case anymore. My shop is currently working on mini testing and approval. As in, the POI said they will approve the mini once we get all of our stuff in order.
Yes, Our POI said the same thing, but then they pulled the mini out of the list of approved devices due to this paragragh in the AC. The reason is that the screen is not as big as paper unless it is zoomed, but then it dont show the whole plate at once. So it was pulled. Each FSDO may have a different interpatation of the paragragh. But better to find out for sure now than than to buy a whole fleet of mini's that you cant use down the road.
http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC 20-173.pdf
(2) Screen Size and Resolution. When utilizing the EFB to replace paper products,
the screen size and resolution should be designed to display information in a comparable manner
to paper aeronautical charts and the data it is intended to replace. For example, the screen should
be able to display a standard instrument approach procedure (IAP) chart in an acceptable
aeronautical chart format similar to a published paper chart. The screen should be large enough
to show the entire IAP chart at once, with the equivalent degree of legibility and clarity as a
paper chart. This is not meant to preclude panning and zooming features, but is intended to
prevent a workload increase during the approach phase of flight. Alternate representations of
IAP and other navigation charts will need to be evaluated by the FAA Aircraft Evaluation
Groups (AEG).