I think that the picture Zaphod linked to - the one with the oddity, is a "replica" or something of the sort. I don't believe that is the captured
(or perhaps conveniently downed) drone, for a couple of reasons that I will elaborate on in a moment.
Having done some digging into this anomaly.. the whole landing gear issue, lack of bays for said landing gear etc. I did find an image that sort of
jives with the "odd RQ-170." It's the best one that shows the underside, and there are some similarities methinks.
That one also appears to have the same issues, and it apparently was used on a float display... according to this:
Fars News Link
There are other images on the net that show this, but from a slightly overhead view.
So, ultimately I think it's is a propaganda piece, or display model for Iran.
The first video that came out regarding this - the one that looked like it was filmed in a gymnasium (with the underside hidden) probably is the real
aircraft. Doubtful that it would be paraded around, as it's probably in a very secure location being examined.
The RQ-170 went down December 4th 2011 according to wiki (I know) but is that accurate?
The RQ-170 "gymnasium model" video came out December 8th or 9th 2011, right?
Lastly the RQ-170 "float display model" was February 11th 2012.
Pretty fast to work up a visually similar scale model, if that is really
what we are seeing here.
Is it possible that this drone was downed earlier than had been reported?
And, there is the alternative angle... being this particular drone was flown just like we see it, with fixed landing gear. Perhaps that is why the
underside is obscured in the video release, for saving face after stating you just acquired a highly classified stealth drone, just with some rather
odd non-functional properties.
Either way you look at it, it is strange.