I've never been a fan of Infection in Halo 3 or Reach. I've yet to even play Flood and I have no intention to. As Bloody Initiate said, it's just too stupid and unbalanced for me to enjoy it.
I could enjoy a game of Zombies every now and then back in the Halo 2 days, but even then, it was unfair because most people preferred to play on Foundation, which was a horrible map for it. The human team would always go into the room with all the crates and melee the crates into the doorway which made it impossible for the zombie team to get in without having to jump onto the crates and crouch under the doorway to get in to kill the humans. While crouch walking over the crates, the zombies were then vulnerable (because you move very slowly when crouching) and would be blasted by shotguns. Naturally it was very rare for the zombie team to win on Foundation and since Foundation was the most popular map for the gametype, it was extremely unbalanced.
Long story short, I hate Infection/Flood and I'm not surprised to hear that it's unbalanced in Halo 4.