I thought it was well written, with scenarios that were new, clever, and inventive. The zero gravity effects, the additional "human" xenomorph, the massive flood of facehuggers for example. The references to the original "technology" and prior lines repeated, along with Ian Holm's A.I. cameo were good for fans. This time the android is vulnerable and likeable.
Yes, the movie is worth your time and money. It was over too quickly for me.