Cisco Career Path

DSP

I work for a consulting company as a Network Voice Engineer. They are looking for me to pick a specialty to focus on. I am curious what people suggest. I am fairly impartial to what technologies I prefer to work on. I am looking for something that there is still going to be a demand for in the future, and pays the big bucks. Here is a list of the technologies I can specialize in:
Security
Unity
IPCC
Wireless
Video

All opinions are appreciated!

Thanks,