In #1852, I suggested

... the above made me wonder whether for internal use we should simply make our own MaskedArray subclass in which we override some of the behaviour; this helps make sure we do not have to take the peculiarities into account in every subclass we construct (the comments in MaskedColumn show this has been a fun aspect...), and will also make it easier to send PRs to numpy (I saw @taldcroft had a few, and I've been making some myself as well).

Aside: from my last PR it is clear the numpy people would like to move MaskedArray to the new array_ufunc functionality (which will be a big benefit for Quantity as well). This is a chance to help get the implementation right.

The ding-ding-ding in #1471 made me feel this probably is something we should do -- hence I decided to make it its own issue.

EDIT (2014-01-17): Possibly, we should even have our own ndarray subclass, as this would help with, e.g., pickling of additional attributes (see #1961).