which is better BCA or B.Sc(IT) ?

BCA is more of practical oriented and is more suitable for those who want to go for MCA and hardcore programming. While IT is more of academic and covers more of IT related concepts. It is more suitable for those who prefer roles like EDP management, MIS Management or IT management or would prefer careers in Database Administartion or Network Administartion. Otherwise both are considered equivalent and get same opportunites for job.

Hope this helps.