The first question which comes to mind when we consider Camouflage as a possibility (since all we know at this alpha stage is that Blizzard is just considering it and testing it out), is whether or not hunters should have some sort of stealth ability. Does the advantage of sniping make such an ability overpowered?
As far as PvP is concerned, currently the closest thing we have to sniping in the game is a rogue's Ambush, and since that's within melee range, obviously it's not the same. Being able to unleash a powerful attack while hidden and at a longer range makes a hunter's snipe all the more dangerous, because your enemy can't just turn around and start smacking away at you. First they have to look around and try to find you wherever you are, which could be hard in those cases where hunters make the best possible use of terrain to conceal themselves in a bush, behind a tree, or other such objects which obscure enemy players' vision but not your character's line of sight. Then, once you've found the hunter sniping at you, you need to close range to him, which, if the hunter has laid his traps carefully, could be rather difficult.
One of the ways that Blizzard may be thinking of balancing Camouflage is to use it as a way to reset the battle, like Vanish and Cloak of Shadows do. This way, hunters would have to choose if they should use it as an opening ability or as an escape ability later on midway through the battle, after the enemies are well aware of your potential threat.
Personally, although I like the idea of hunters having some sort of escape, I don't like these two elements mixed together in this way. I would much rather see Camouflage as an ability purely geared towards catching an enemy unaware, maybe even adding a certain percentage of damage to that first attack as you come out of Camouflage too. The idea of camouflage that the ability is based on lends itself more to this element of surprise than it does to some sort of escape. Also, it doesn't seem right to me that hunters should be able to sneak around and skip past certain PvE monsters in the same way that rogues can. Perhaps if this worked better when you stand still, and less well when moving, it would fit in with the theme better, and also encourage setting up ambushes for your enemy to fall into -- which feels very hunter-like -- rather than sneaking up to where the enemy is, as a rogue would do.
The other limitation that helps moderate the ability its 5-minute cooldown. This would prevent hunters from using it continuously, which feels right to me. It should involve a good bit of planning to use well, not something hunters start off with in every battle. Hunters are not, after all, a stealth-based class -- even if we get something like stealth in one form or another, it should never define our class in the same way that it defines rogues. Rather, it should help us do what we already do even better, and open new doors based on our existing tactics and strategies.
That said, the other element of this possible ability, which clears all physical and magical debuffs, is also something that fits well with what hunters are. Feign Death removes all threat, Readiness resets all our cooldowns, and The Beast Within makes us unstoppable unless killed. Something to free us from debuffs is a logical step, but I would like it to be separate from Camouflage, possibly tied with Feign Death in some way (though certainly not useable every 30 seconds).
To be fair, I seriously doubt this ability will go live without any serious changes, if it goes live at all. I've already mentioned the kinds of changes I would suggest, but it's anyone's guess what Blizzard will actually do.