It is WAY low. I could easily agree with a 6 with possibility of going up to a 7. The point of course is that the IGN review seemed just over the top negative and didn't really reflect someone giving a slightly opinionated, yet objective review of the game.
The heading of the review says it all..."Spider-man Edge of Time. Not worth your time." It's not even a creative use of the word time. He is basically saying flat out, this game sucks. Everyone is entitled to their opinions but holy flaming anger batman he seems more like a disgruntled ex-Activision employee than anything else.
It doesn't really matter. What matters is that I rather enjoyed the game, very much actually. I was just very surprised to see a score of 4.5. Not what I was expecting.