First thoughts:
Camerupt: Stay in NU. Although it hits hella hard, its speed definitely limits its ability to be effective in NU, combined with a lack of recovery and the fact that it's affected by all forms of entry hazards. It also has relevant counters in the tier being mantine, audino can CM on it, and offensive pressure.
Typh: Stay in NU. This thing isn't as much a problem as it is an annoyance. Dealing with it in the teambuilder is harder than dealing with it on the battlefield, but neither are too tough. Only case I see for it is overcentralization, which is pretty weak since it wasn't even the most used mon in the tier last month. :]
I'm gonna pile onto the no-ban argument with a more well constructed post than this one. :^]
Typhlosion: I really don't see the big issue with Typhlosion. Most of the argument's I've seen on here point to the wallbreaking potential of Typhlosion, which is pretty viable with a choice specs set. However, when people bring up the fact that there are switch ins to the specs set (Mantine, Hariyama, Flash Fire users, Rhydon, Lanturn, Grumpig, AV Magmortar, SpDef Frog, Regirock, Archeops, Zwei), the pro-ban argument is that now that Typhlosion with great wall breaking potential is now forgoing that trait to act as a lure, running the Charcoal-Wisp set. While both of these sets are viable, it seems as though people assume Typhlosion is at all times Scarfed, Specs, and the lure set with both Blaze and Flash Fire, which simply isn't the case. Regardless, each of these sets has counters in the metagame that can fit onto any team archetype, and perform roles outside of beating "fire spam".
Although it is a good Pokemon, the meta isn't being particularly kind to it right now:
1. Hazards always play a huge role in NU, they always will. Spikes and T-spikes and hazards in general are more important here than in any tier baring maybe ubers.
Typh cannot afford to switch in on pretty much anything in this meta, and it also cannot afford to switch in on hazards throughout the match, as it weakens it's eruption significantly, which is it's main selling point. Also, it's difficult to remove hazards right now as the premier defogger (mantine) is relatively easily pressured/loses to some of the best SR mons in the tier. Claydol is a good spinner, but it kills momentum, and offense has no issue with it since Mismagious exists.
2. The meta is trending towards speed. Tauros, Sneasel, and Archeops are all extremely popular right now because they're really good. For Typh to even outpace these things it require scarf, and Scarf Typh is weak as shit and shouldn't be used in general.
3. Priority is everywhere.
My least favorite argument for Typhs banning is when people say that its coverage options destroy it's "counters". For the most part this isn't true, and more importantly, assuming the Typhlosion user always predicts correctly while the person switching in on the Typh always predicts incorrectly is ludicrous. Good players scout, make switches that won't jeopardize their chances of winning if they predict the set wrong (which you can predict the set in team preview 90% of the time, it's not really an unpredictable mon, look at Mesprit if you want unpredictable), and good players have mons that will punish Typh for locking into a support move. and if they're not choiced you lose your wall breaking powers. So, it's a good mon, but it's not nearly as good as people make it out to be.
Camerupt: This thing is annoying as hell, does that make it ban-worthy? Definitely not. Camerupt actually provides NU with some pretty cool stuff, specifically a mon on balance that can set up rocks on Xatu. Camerupt hits like a truck, but it doesn't really get that many opportunities to switch in throughout the game due to its poor defensive typing, the fact that all hazards effect it, and that it's slow enough that it has to take 2 hits before it can attack. In addition, it has no recovery, so it gets worn down extremely quickly over the course of a game. Apparently Will-o-Wisp makes this mon broken (ban pyroar n_n). It's speed is what's killer about it. It really just...is slow as dirt. And you generally have to either sack something, or run dedicated voltturn to get it in safely. The only team archetype that makes me question Camerupt is TR, but TR is something you generally just have to play around anyway because everything hits so hard on it. If this goes, I can understand it though, since we've never really had a wallbreaker like this.
Don't ban Typh.