According to culture of Indian engineering colleges there is no main difference in these two Streams. Same Subjects for both, same teachers for both and same way of teaching for both.
But, if you see closely, IT is more into Core Development. Many colleges who knows the difference they have their different curriculum for both.
For eg, If you study in a good colleges they will have:
- More into practical for IT and less into Practical for CS.
- IT has more subjects as they can go to Hardware, Networking, Telecommunications, software and many more.
- In CS you will be aware of Software, Hardware, Networking and Microprocessor. As you are gonna be a CS specialist very soon.
- Computer science students will study mostly in classrooms(less labs) when IT guys will be doing LAB works and Classrooms works.
- Labs in IT which is missing in CS: Adobe Flash, Multimedia, DBA(Not Database lab, its administration. IT has both- DBA and Database lab), Information security,