"Snakes on a Plane" looks like a parody of a real scary movie.
Unfortunately it is not meant to be funny, it is meant to be scary. In the end it will just be a bad movie, but it does have the making of being a cult classic.
I kind of think so, too. Or maybe, as others have noted, it just adds a bit of humor or it doesn't take itself too seriously, like in Gremlins. Either way, I'd love to see it, just having the inimitable Samuel L. Jackson in it makes it worth the ticket price, but I don't think I'm up for the shots of snakes lunging, from the audience point of view, full screen right in our faces, as I saw in a TV commercial. Shudder.