First-thing, I will say that Edge of Time seems to have the cleanest and smoothest implementation of the system's 3D screen that I've seen yet. Pretty much every other game causes my eyes to start losing focus or aching within a half hour. The usual fix for this is to simple turn off the 3D aspect of the screen and keep going. Edge of Time, on the other hand, not only let me play much longer with the feature turned on, but the depth and dimension being portrayed just seemed all around better.
The rest of the visuals for the game is a bit of a mixed bag. I was surprised to realize that the 3DS version of this game wasn't another release of the standard DS version, but was actually the same game you will find on the consoles. I'm not saying that it has the same storyline, I'm saying it's the same game. There are some minor tweaks from what I observed while watching Geck0 play the PS3 version, but they were mostly cosmetic. For instance, where the Spider-Man you weren't controlling would appear in a corner of the screen for the console versions, the 3DS one puts the alternate Spidey on the bottom screen.
As impressed as I was that the developers put the full console version of the game onto a handheld, it also led to a few problems. Let's just say that there are quite a few times when the machine is trying to do just a bit more work than it can manage. There are times in the game when the enemies will start popping around the screen. If it were a pure framerate issue, then it would be more obvious since moving around would show similar jumping, but instead, what you see is flailing tentacles that look like they have very few frames of animation or enemies on the other side of the room disappearing and reappearing slightly closer as they run towards you. The game isn't broken, it's still playable, but when you get a lot of activity going on around you, these problems become very apparent.
Audio, on the other hand, is all good. Not only is the game fully voiced (again, this isn't just a hand-held version released alongside the bigger games like normal, its the full game) but there are quite a few good actors behind their characters. Josh Keaton and Christopher Daniel Barnes return from Shattered Dimensions to play Spider-Men, but this time Keaton portrays classic Spidey and Barnes switches from Noir to 2099. Add to that Val Kilmer as the game's main antagonist, Katee Sackhofff (Battlestar Galactica) as Black Cat 2099 and Smallville's Laura Vandervoort as Mary Jane and you have a great cast, one that you simply don't see on Nintendo handheld systems.