We've all seen what the other two scholar professions can do. Necromancers are beasts when it comes to control because of their large/multiple health pools, healing skills, and cooldowns. Elementalists have some interesting ways to prevent damage in Earth Attunement like Sandstorm and Magnetic Aura. We've also seen control at its best with the Guardian walls, rings, and bubbles. I'm having trouble wrapping my head around what exactly a Mesmer would do as Control, given the kinds of skills they had in the original Guild Wars. I doubt we'll see more traditional tanking skills like Shield Stance.
What should I expect from the Mesmer? Maybe a veteran of GW1 can enlighten me.
I'm no GW1 expert or veteran, but from all the game I've played thus far, I can say they will probably play more like a psionic/magical version of the Engineer. Multiple skills, multiple conditions to throw on people, a ton of CC's that also either attach conditions/hurt the mob(s)/help your allies. Maybe also throw in some illusions (big maybe) and some other fun goodies.
But I'm crossing my fingers, waiting also to see what they've come out to be.
in the origonal Mesmer controll fell into one of a few catagories. Snares, skill interupts/lockouts, Energy denial, and skills that punished the victem for acting. Snares are prety self explanitory and are already represented in GW2. Interupts and lockouts not so much, the closest examples would be the various knock down/back and stun skills. Probably would not be a good idea to build a class specificly around that. Energy denial is a no go as that is out of the game unless its as a skill that reduces dodgeing. Punishment skills do have some merit but as hexes are gone they'd have to do it with conditions and they have not shown any condition types so far that would sufice. If you dont know what I mean by punishment skills here are a couple examples from the first game. EMPATHY caused the target to take damage every tiem they attacked with a melee swing while BACKFIRE would blast a caster every tiem they cast a spell, other hexes would cause your next spell to have a long CD. They also had a few spells that punished inaction, Wastrals worry, if you dont use a skill in 4 seconds you take damage, Wastrals demise you and everybody around you takes increasing damage for 10s till you use a skill. Combineing a wastral skill with a punishing skill forced the target to choose which effect to get blasted with while a lockout skill could force them to eat a wastral's full effect.
Unfortunatly alot of the controll mesmers had in the origonal either dont work without alot of new conditions being added or are already quite well represented in other classes like the necro. If I had to imagian what they'd do with mesmers without hexes I'd look at the sorcerer class from DAoC if they added a disorient type condition unique to mesmers. That said sorcerers often went from masivly OP to a joke depending on how they nerfed their Mez spells in pvp. Nobody likes looseing controll of their character and it gets really bad if its for a long duration.