Batman Beyond is a
Spiderman analogue. He is an
angst-ridden
teen with
superhuman abilities (in McGinnis' case, conferred by the
armor he wears) who
fights
crime in
secret, and suffers for his
time spent doing so instead of getting good grades or being around when his
girlfriend wants him to be.
The animators and writers involved in the show know this perfectly well. If you watch carefully, you can catch many visual hints and in-jokes that tip their hand. From the three-frame, primary-color dancing scene at the nightclub in the opening credits (which is almost a shot-for-shot from the 1960's Spiderman cartoon) to a number of the poses McGinnis strikes, they show up in pretty much every episode.
No aspect of the show makes this more obvious, though, than the villains he contends with. The Spellbinder is essentially Mysterio. Inque is a female Venom. The Terrific Trio are the Fantastic Four minus one. Etc.
It seems, though, that the similarities (at least in terms of the artwork) are meant more as fun-loving pokes and tributes more than anything else. The show is too well-made and skillfully executed to be relegated to the nasty realm of the knock-off.