OK, here's my review.
1.) It's silly but it's not especially campy. The humor is all in the absurdity of the scenario.
2.) It's technically OK but you can definitely tell when a live snake was used in a scene and when CGI snakes were used. The CGI snakes had hints of "video game character" all over them.
3.) Nobody could have pulled this movie off but Samuel L. Jackson. In a lot of respects he's what elevates this above and beyond the schlock barrier. Great acting, with little hints of that good comedic sense he displayed at Comic Con when they did the panel.
4.) The director really got acquainted with Sam Raimi's style of directing when he did this. In fact I think the only person who could have made this better would have been Sam Raimi. Maybe they'll hire him when they do the inevitable sequels from Special Agent Flynn's case file.
5.) If you want a good idea of what you are in for, think the original Poseidon Adventure or the Airport movies instead of Airplane! This is a reboot of the '70s staple, the disaster film, not a spoof. If you've seen any of the originals from the period you'll know what you are looking at.
6.) I'm sure getting Keanu Reeves to portray the surf rat dude would have cost way too much for the budget. But that role was made for him. Maybe he'd be a bit too old for the role by now. In that case, the guy who got the role was just fine.
7.) No matter how prepared you are for the catch phrase, it's still effective. Although in my opinion the best line is actually "Fucking snake! Get off my dick!"
Was it worth the $15 for the both of us? Yeah, it was. Is it high art? Nope. Is it a mythological journey with a universal message? No freaking way. It's just your basic grindhouse disaster movie and if you come looking for anything else you will be disappointed. However, if you come looking for your basic grindhouse disaster movie you will be richly rewarded.