It's sorta a mix of the comic and cartoon. Like you, I was a fan of the comic book (the only comic I read), and not so much the cartoon. The plot reminds me of the cartoon min series plots. Extremely over the top. In many ways, it's like a live action cartoon. I liked it anyways though. It's just a roller coaster ride of action. There are certainly some points where I wasn't expecting to see, with some certain shots of violence. Check your belief at the door, and just enjoy Joes and Cobra (well, sorta) kick the snot out of each other for a couple hours.
There are liberties taken that I am not fond of, but overall, it was enjoyable and fun. That's what gets me the most about some people who have seen it...they say it was a lot of fun but they "hate it" still.
They now hate fun if it wasn't the fun they remembered?
I liked it for what it was...over the top, unbelievable action sequences, and a lot of fun.
Some people don't like a certain plot point of the Snake/Tommy origin, but I don't think they were really paying attention to what Storm Shadow had alluded to when he spoke. What he says when he fights SE is important in that context. I think the sequel will take that and run with it, satisfying comic fans.