You'd've got enough from the link given in the above post, but i'd like to give my opinion... I too like java very much, and i got certified for only 1 reason, the knowledge and understanding of the fundamentals....
scjp is quite good for grasping the basics firmly, and once i got certified, im surprised how many people in my office come to me for clearing their fundamental doubts, and how well im able to answer them... i wont say scjp is going to get u a job in sun microsystems, NO. But definitely, u get a good satisfaction once u r done...
regarding the exam, i suggest 1.4, the new 1... one reason, keeping up with the latest.. another reason, its easier to prepare

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