i render to SONY AVC at High profile, 20Mbps - i use Vegas. i always loose serious amount of shadow details, and such. (after uploading)
Vegas plays/codes the same footage differently than AfterEffects. in AE its already darker, more saturated in some ways (especially the greens)

Canon footage seems to be .601 - at least Cineform corrects it when converting.
i thought a proper .709 footage gonna be ok on YouTube - but i was wrong. NEX5n footage is darker too.
i wish i could have the very same uploaded to these video sites.