The most noticeable appearance of fan service comes in the game's voices. Since Shattered Dimensions spans four different versions of Spider-Man, it seems like the decision to choose which previous voice-actor would take the lead role was made simpler. Instead of focusing on one previous holder of the title character, the developers at Beenox actually approached the four most recent voice actors and used them.
Taking up the role of the main universe, here referred to as Amazing Spider-Man, is Neil Patrick Harris who played in the 2003 series, Spider-Man: The New Animated Series. My personal favorite, Christopher Daniel Barnes takes on the role of the license's newest line, Spider-Man Noir, and he comes from the 1994 series, Spider-Man: The Animated Series. The 2099 version of Spidey is voiced by Spider-Man and His Amazing Friends's Dan Gilvezan and Ultimate Spider-Man's voice is done by the most recent show's main actor, Josh Keaton, this newest show being The Spectacular Spider-Man.
Each Spidey is portrayed very well, and each has a noticeably different attitude. Amazing is more of the classic one-liner Spidey most fans will recognize, while Noir takes on a darker tone with a 1930's dialect. It isn't just the Spider-Men though that have fan-favorite voices. Many of the villains are returning actors from previous Marvel-related products reprising their roles. Nolan North takes up Deadpool again, while Jim Cummings plays both Kraven and Scorpion.
Of course, the visuals are nothing to sneeze at either. Each universe has a fairly unique look to it. Amazing seems to be straight from the comic books, complete with a paper texture, while Ultimate uses the darker blacks and grittier style from that universe. 2099 is all lights and flash and Noir is almost always portrayed as a stark black-and-white, and even when you creep into the light to let some color show, they are far more washed out than in the other universes.