For those unfamiliar with the latter:
http://en.wikipedia.org/wiki/Discovery_Institute
I would posit that the DI has a more invasive agenda than the MI - to sneak religion into the classroom under the guise of "intelligent design" - but other than that they're pretty similar. Both are deeply anti-intellectual but position themselves to true believers as sources of legitimate academic research. Both Institutes are full of degreed persons publishing outside the area of their expertise. Both have a token scholar with a PhD that's actually topically relevant - John Gee, Egyptologist for the MI, and Michael Behe, biochemist for the DI. Both of those token scholars, though holding legitimate degrees, are cranks operating on the fringes of their fields.
Both the MI and the DI fight against legitimate scholarship. The MI does its best to counter legitimate Egyptology, New World archeology, and studies of Native American population genetics. The DI fights primarily against evolutionary biology. Neither have any academic/scientific credibility, but the DI, due to its more visible presence, has seen a lot more scholarly criticism.

