joker97: some dumb questions after sneaking into those sites during work ...
1) the cheap cases say no front usb 3 but doesn't actually say there is rear usb 3 - is that a given?
The motherboard is the only thing that matters for rear usb 3 ports so the case is irrelevant.
joker97:2) can a mini atx mobo fit mini itx
No, Atx will fit Atx,mAtx or iAtx. mAtx will fit mAtx or iAtx. iAtx will only fit iAtx.
joker97:3) do the trinity/richland in general use less power than the i3/i5?
It depends on the particular processor but looking at the 5600k its tdp is higher than the Intel i5's.
Tdp is not neccessarily what will be used all the time. Looking at energy usage over time over at Tech Report performing a task the Intel's use less power than any of the Amd's but it's probably not significant enough to matter.
joker97:4) will the haswell/ivy bridge i3s be good enough for 1080p video?
I would think so but haven't tested this.