At max rank, the Q does, total 330 (+.7) AP. Certainly a lot of damage. Not a totally unheard of amount of damage. It's a single target spell. In terms of it's actually base value and ratio, it's in line with his lazer. More damage than a single lazer hit, less than if the lazer hits aftershock. The main difference is that it has a low cooldown, and it has synergy with lichbane.
Lichbane is what makes Q do an obscene amount of damage. But lichbane is an extremely aggressive item to fit into Viktor's build. He only has 4 item slots to fill with AP items. Viktor really likes all of the following items: Llichbane, Rylais, Zhonyas, Void Staff, Rabadons, and situationally, Abyssal scepter. Viktor actually has to make some pretty big sacrifices to fit in Lichbane. It's probably either going to replace rylais (a health item) or Zhonyas/Abyssal (more defensive items).
Viktor cannot burst people with just his Q. He can definitely burst people with his Q/Lazer, which can be cast together very quickly. But that's a separate matter.
As for new vs. old viktor. Pre-rework viktor was borderline oppressive in lane. His Q offered a poor risk/reward tradeoff in late game team fights, but it had a very high base value, cost, like, 30 mana, and had a decent range for a fire-and-forget nuke. I remember dumping 2 early points in it in lane and just spamming it 24/7 on lane opponents. The lazer also had lower counterplay and synergyzed insanely well with Liandries, which meant rushing haunting guise (a super strong early/mid game item).
New Viktor is pretty bad in lane, but scales into some of the highest damage output in the game. But he's also squishy and low range.
I mean, do you think current Viktor is OP? He has had a terrible win rate since the lazer nerf. I've been playing him religiously since S2, and I've been having a lot of trouble finding consistent success on him. He's still a late game monster, but he legitimately has to work his ass off to get there gracefully. Though some of his concerns are meta-specific (lots of divey bruisers top and lots of assassins mid).
In any case, this is all irrelevant, because it looks like Riot is going ahead with these Viktor changes that literally no one asked for, and no one on the boards seems to particularly like.