Hey, I have to admit that I sort of enjoy it and not in some ironic way. I don't think it was really all that needed after what happened at the end of the 3rd one and would be hesitant to call it a great movie, even a very good one, but it has a lot of interesting ideas and quite a few fantastic moments. What I don't agree with most people is that the tone ruins the film. If all three previous movies maintained a very specific style and tone then obviously Resurrection would stick out like a sore thumb, but thing is that with each new movie Alien franchise went totally different ways and the silly, comic tone here is just one of them. That said, I will be first to admit that most of the humor, at least the verbal one, fails. By now all of you know Joss Whedon's signature writing style and it needs a director that understand how to deliver it right. Jeunet (who didn't even speak English at the time) fails pretty much with every one-liner and, boy, this movie has tons of them.
There are many more problems with Alien: Resurrection, many concerning Ripley character, but there are many things that they did right and by the time the end credits start to roll, I didn't feel like I was watching a total trainwreck or a lazy exercise in mediocrity. It is way too bizarre, strangely touching and entertaining for that.