After many years as a system engineer in both enduser as well as field services I find that it's not very rewarding career being a unix engineer in either. I find that the best place if you want a career in is either application development or doing networks security.

As a network security engineer you have to learn new things all the time as new threats emerge but in reality once the corporation network is setup and running in production there is very little to do except every once in the while install some patch add some rules on the firewall, maybe every once in a while your network gets hit by a new worm and you are busy but most times I observe network engineers are quite free, and you most certainly won't see them arguing with application people over application performance problems as compare to the system administrator.

Also a system person in an enduser environ, you do not bring much value as compares to a application developer. What you are doing is just maintaining the existing infrastructure, sure maybe you rollout a new system every now and then but that's what your mgt expects of you anyways?

The application developer on the other hand brings in a lot of value in terms being able to understand the business needs and requirements and delivering those needs hence when it comes to getting bonuses better apraisals, pay increments the application guy usually gets more. You will find that in many environments the system and application are always fighting each other and very often the application guy will get the ear of the mgt to see things his/her way and thats the reality. In many environments I've been to i've observed that the applicaiton guy if he/she stays long will eventually become the Head of IT department.

In vendor field services environment here you get to touch many systems but the learning curve is very steep and competition is very intense and the work is like preassure cooker, you're busy all the time, doing standby's, upgrades for paying customers implementating new projects sometimes even handling more than 5 projects on hand concurrently But not all engineers are built the same, some are very good in storages, some good at servers, some network oriented but very few are all rounders, you won't have any applicaition developers to fight with instead you are competiting your careers with each other and only the very best engineers get rewarded.

One last thing, these days when corporations are outsourcing for cheaper services you will find that most often jobs that go are mostly system related , application usually not much affected.

my 2 cents