What is it?
A 32 page black and white softcover book with a color cover. It contains character stats for use with TSR's Marvel Super Heroes RPG. For the most part it has two characters per page, with the exception of full page write-ups for the King Pin and Spider-Man, and a two page spread of supporting cast characters that contains very short write-ups for twelve characters, including Aunt May, J. Jonah Jameson, Misty Knight, and Colleen Wing.
I won't list them all, but some characters covererd include: Power Man and Iron Fist, Cloak and Dagger, many memebers of the Serpent Society, Swarm, Scorpion, Mysterio, Moon Knight, and Mister Hyde.
What's good about it?
It's got stats for characters not covered in other books (up to the point that it came out). It's well organized (alphabetical by the character's costumed name). The visual presentation works well in most cases. It's got enough information to explain some things I didn't know before, like Hammerhead is an amnesiac who based his personality and outlook on old gangster films; I always wondered why he seemd like such an anachronism.
What's not quite so good?
The writeups are so short on history and personality information that it doesn't really replace checking The Official handbook of the Marvel Universe or back issues before using characters presented here. Also, this is just my opinion, but I didn't like the illustration for Elektra.
What the ....? moments
Villains in the Marvel Super Heroes game are supposed to have negative Popularity. There's a few with positive Popularity. What's even weirder is how low the Popularity is for Power Man and Iron Fist (20 each) compared with Kingpin (31), Kraven (33), Taskmaster (30), Black Widow (30), Daredevil (42), or Spider-Man (40). This is during an era where J. Jonah Jameson is still publishing anti-Spider-man editorials.
This book must have come out during an odd moment in Marvel continuity because there is no mention at all of The Punisher's name being Frank Castle. It mentions his history as a marine and his origin but it says real name unrevealed.
Who should get it?
Firstly, since it's for the Marvel Super Heroes RPG, one should be at least mildly interested in that game. Secondly, since it's weighted at least a little towards villain stats, it is probably more of a GM (Marvel Super Heroes RPG calls GMs Judges) resource than a player resource. Thirdly, it mostly concentrates on characters who make their home in Marvel New York, so GMs running a game set mainly in Wakanda or Latveria might have a little less need of Concrete Jungle.