It depends on what you´re looking for... In my opnion security pays the most here... But Cisco PIX is not the only option, so... CCIP is also a good way to follow, and off course, CCVP IP Telephony... Most bussiness of today require that... And also allows you to open your own business to support this kind of service...
I´d like security the most, but in order to attend my company needs, I´m going to IP Telephony... I just passed the CVOICE, and needs two more (plus CCNP) to get there... total of 6 more exams...
If I were you, I would choose the one you like the most, not the one that pays more, it´s not good to receive lots of money, and do something that you hate it!

Cheers!