Welcome to Javaranch !!!
i would suggest -- keep images iin a directory on server.
Reasons
a. images (facebook / orkut image) are static
b. Images are not tied to any user (means every user will see same image of facebook / orkut etc)
c. easier to change images in a directory if required
d. saving image for each user in databse using BLOB/CLOB type is not a good idea
~ abhay
Oracle certified JPA Developer (1Z0-898),Oracle certified Java 8 Programmer I (1Z0-808), Oracle Java Web Service Developer (1z0-897), Oracle certified Java 7 Programmer, SCJA 1.0, SCJP 5.0, SCWCD 5.0, Oracle SQL Fundamentals I, CIW Certified Ecommerce specialist