Mainly what Kalocin said, the job changes have given and taken away. And a lot of people are just salty with some of the changes for the job they've played for years.

Monk, my favorite, is very simple and very fast DPS. all the attacks gain damage from doing positionals correctly (flank/rear) based on the attack. Most of the potencies for the attacks are lower then the other melee but the rate of attacks you do is much higher. Its like a machine gun just constantly hitting in succession with some powerful attacks you can use when available.

Dragoon, previously loved for being the simplest melee DPS in terms of rotation, still hits like a truck and has some really cool and flashy skills. I love playing this class and building up to a massive jump damage.

Ninja, the ninja changes and additions really help boost that ninja feeling. Weaving in Jutsu along with your rotation, summoning a flame spitting toad, and all the flips flips flips. Ninja is a fairly bursty melee DPS in y eyes and its really fun to play if you like that sort of thing. But the rotation is a tad more complex then the previous two.

Samurai, the newest swordsman, does a ton, and I mean a ton of damage. It's signature move, Midare Setsugekka, is one of the highest potency attacks in the game when paired with the personal buff in Samurais toolkit. Samurai relies on balancing Kenki and Sen through your combos to build up to powerful finisher moves. Although the playstyle is very straightforward and simple, its very fun to play.