Spider-Man #700

I saw this alternate cover to the upcoming Amazing Spider-Man #700 on tumblr and I had to post it here. It's got to be one of the coolest covers I've ever seen. For those not in the know, the New York skyline Spidey is swinging over is comprised of the most notable artists and writers for ASM over the last 50 years.

I'm not sure if this is one of those 1-50 variants that's impossible to get or not. Hopefully I can get my grubby little hands on this without having to take out a second mortgage on the house.