I've done quite a few matches so far, and Sticky Web as a concept is just amazing. It single handedly makes Galvantula a viable Pokemon! I can't imagine Sticky Web being that common, because Galvantula offers very little outside of it (and the best spinner, Excadrill, hard walls it). But i believe that just the threat of Sticky Web will be enough to have some large effects on the metagame.
For one, I think the amount of grounded Scarfers will fall significantly. Scarf Genesect won't be nearly as common, nor will Terrakion, Garchomp etc. Instead, we'll see an increase in Scarfers that aren't hit by Sticky Web, so Rotom-W and the like.
An Increase in Taunt leads again, particularly sash leads like Aero. Galvy is fast, but not so fast that nothing can outspeed it, anything that can potentially remove it before it can set up Sticky Web will be much more common.
For one, I think the amount of grounded Scarfers will fall significantly. Scarf Genesect won't be nearly as common, nor will Terrakion, Garchomp etc. Instead, we'll see an increase in Scarfers that aren't hit by Sticky Web, so Rotom-W and the like.
An Increase in Taunt leads again, particularly sash leads like Aero. Galvy is fast, but not so fast that nothing can outspeed it, anything that can potentially remove it before it can set up Sticky Web will be much more common.