Personally, I like both crochet and knitting. each technique has strengths and weaknesses and both are important skills to have. I find crochet much easier to understand and manipuate; but the projects I want to make right now are knit. (for the record, I learned knitting first, but learned crochet faster)
I think people get a mental block when having to switch gears between the two. maybe it has to do with the muscle memory or rhythm you get in to with knitting, it isn't easily switched to the different rhythm and yarn handling of crochet.
Then there is the association of crochet with the weird stuff of the 70's and all the toilet paper covers in grandmas house. you often hear that knitters call crochet the "c word" as if it is less worthy. or only pick up a hook to fix dropped knit stitches.
most people I know either do one or the other 90% of the time. I don't know why really.... but I like both.
did I say one project at a time?