sir,

my iitjee rank is 1527, please suggest me the best option

to choose with regards to future demand and placement.

Hi Akash,

You will get branches like mech. , Chem . and dual in Mech. CS. in old IIT's . Apart from that you will have chance to get almost any branch in the New iit's 

for details check out below links 

http://www.askiitians.com/iits-2009-2010-opening-and-closing-rank.aspx

Cutoff in new IITs  check the link give below :

http://jee.iitd.ac.in/openclose09.htm    (this link includes the more detail analysis)

for code of the cources check the councelling broucher 2009.

All the best !!!!

Anshul