I got two kittens from the shelter back in early December. They were not from the same litter but they get along great. Lloyd is very friendly, laid back, and loves petting, doesn't mind being picked up, etc. Harry on the other hand, not so much. He basically hid from us in the basement the first couple of months. We finally blocked off the basement and slowly over the last 3-4 months he has gradually gotten more comfortable around us. He still runs from the room if he's surprised or if new people come over. But for the most part he seems relaxed, he plays with toys, eats treats out of my hands, rolls over on his back, and meows at me. He'll often follow me around and if I'm in the kitchen often times he just sits there right behind me. However, he does NOT want to be touched. If you hold your hand out, he will walk right up and sniff it - and then back away and/or swipe at you. Also, when I'm getting his food ready in the morning and evening sometimes he'll come up and nip at my legs. What's the deal? I know it still hasn't been very long in cat terms but it does seem like his "progress" has stalled somewhat. Maybe he'll always be a furry goldfish, and that's fine. I'm just curious if others have seen this type of behavior and if there's anything I should be doing.
I agree with all the above members that every cat is an individual, i.e. some need time and patience to come out of their shell while others like Lloyd are social from the start. Just like people, they are unique in their own way. Harry may warm up as time goes on or he may not but that's okay. You adopted him from the shelter and are giving him a forever home which is what counts so kudos to you. 
Have you tried some interactive play with him when no one else is around? There are a plethora of toys available and perhaps he may take a liking to some of them. Please ignore the title of this Article but it has some great toy recommendations that you might want to try with Harry: 
