Well move-in can be horrible since you never know if it will snow during mid-January. Depending on how many students live on-campus can affect your dorm placement but I'm sure you will be fine. Just be happy if you get a regular room since I know a few people who had to live in temp. housing the entire fall semester. Since people leave after the fall semester due to bad grades, finances, etc. your chance of getting a room is better.
I can't really think of any negatives to starting in the spring other than making friends and not knowing the campus that well. Orientation for spring semester is def. shorter than the one for fall semester. If you go on the SAT Office website you will find info. on spring orientation for new students and transfers.