Charizard finally useful attacker?

I think so. The only "problem" is that Flareon is so ubiquitous that you really don't need a Charizard, although he looks more badass.

I'm still comfortable with Arcanine than Charizard and Flareon specially dealling with the Nurse Defender....

Fire Spin / Overheat is amazing atm, the only problem is that Exeg is dead before Overheat is fully charged :D
But I also suspect they will nerf it within the next 3 months (damage over time?). So I wouldn't power it beyond level 30.

Keep in mind that charizard has double resistance to grass, so if your the grass opponent that you are fighting is much higher level than the charizard, it won't matter that much because those grass attacks do almost no damage (because of the double resistance)

It's a little situational, but basically yes, FS/OH Charizard is second best fire attacker after FS/OH Flareon.

In terms of raw DPS he's a little better than FF/FB Arcanine, but Arcanine has a little more effective HP, so really they are capable of about the same amount of damage before being KO'd.

So that may seem like Arcanine and Charizard are tied for second, but I give the advantage to Charizard though because as an attacker you can use his Flying typing to your advantage. If you put him up against anything that he can resist thanks to his Flying type (anything with Fighting moves, or his double resistance to Grass type moves), that extra resistance would actually make him a better pick than Flareon.