William Gibson didn't actually know much about computers or networks when he wrote Neuromancer (on a manual typewriter IIRC)... ironic given that he coined the word "cyberspace."

And as far as inspiration goes, it's worth noting that Blade Runner came out as William Gibson was finishing Neuromancer, and he almost gave up on it because he was afraid that by the time the book came out people would think he was ripping off the movie.

I don't think the Matrix needs to "credit" Neuromancer as an inspiration, though. The Matrix draws from a lot of sources, but being cyberpunk, inspiration from Neuromancer is a given.