Yes the CCNP only lasts for 3 years. Again, to re-certify though you can just resit one of the CCNP exams. I am in the same situation with my CCSP so i plan to sit the new PIX/ASA exam as i have not seen anything to do with the ASA yet so i am looking forward to it 
Keep in mind though, you can take _ANY_ 642 level exam to recertify for the professional level certs.
My CCNP is coming up for renewal, so I am going to recertify with the CCIP BGP exam and start the CCIP certification process. If you wanted the CCNP/CCIP cert, you could recertify your CCSP with an exam from one of those tracks, instead of re-taking an exam you already passed.
If you are planning on acquiring more than one cert, it is a good idea to use the re-certification process to your advantage, and kill 2 birds with one stone.