Originally Posted by
powerknowledge 
Not to muddy the waters too much with the whole "does the 805 pass component 1080i as HDMI 1080i" discussion, but looking at p.6 of the manual it clearly says this about the 805:
HDMI upconversion of composite video, S-Video,
and component video sources (720p capable)
Whereas for the 875 it says this (same page):
HDMI upconversion of composite video, S-Video,
and component sources (720p, 1080i, 1080p capable)
This clearly indicates that for the 805, any non-HDMI signal upconverted to HDMI will be output at *up to* 720p. The "hidden menu", if it "works" the same as on the 605, can set 720p as the default HDMI output for all non-HDMI sources.
I bring this up because nobody, as yet, has discussed this in relation to what the manual itself says in its most basic overview. (I know: we all skip the basic stuff to get to the interesting stuff; here, though, it's important and most importantly clear).
The implications:
1) If you're hoping to run 1080i/p component in-->HDMI out, you're going to get 720p. All HDMI signals in-->HDMI signals out, however, pass through unaltered.
2) To get 1080i/p over component through the 805, you have to output that signal over component as well (the signal in this case will pass untouched).
3) This should also put to rest the question of whether activating the "hidden menu" disables your ability to have 1080 component-->1080 HDMI passthrough. It can't, and won't, happen this way regardless of what you do or don't do. So, I would presume that anyone thinking that activating this "option" might somehow irrevocably "break" the upscaling/upconverting capacities of the 805 should put this out of mind. In no scenario could the 805 do this anyway.
4) I'm sure this will be immensely disappointing to some. It won't affect me, and I'm still eagerly awaiting my 805 without reservation. But for those with multiple 1080 component-only sources that were hoping for those signals to be passed at full resolution over HDMI, you may want to reconsider your options (from getting an 875 or a different brand receiver without this "quirk" to simply making different connections to/through the 805 and/or your display).
Hope this helps in the decision-making, and that it provides more calm than concern (yeah, right!).