While I tend to agree with the OP I don't think it is that big of a deal except for max level dungeons. You level up so fast and leveling dungeons are so easy it doesn't matter much. Seeing as how Blizzard kind of went out of their way to kill off doing dungeons at max level in MoP, I don't see the point in spending much time worrying about it. As much as I liked doing dungeons in previous expacks, I don't think Blizzard will be taking the game in that direction. While there are a few ways to go about getting valor, the only acceptable end game activity for real character progression is raiding now.
They're going to do it next expansion, I can almost guarantee it. The only reason it hasn't been done yet is because they need to itemize drops off of all the low-level dungeons and will save it for 6.0 since it'll be a big undertaking.