I think that the answer to your question depends on the size of the organization you work for. My first job was working for a larger entitiy supporting over 1800 users. At this location I was only dedicated towards supporting microsoft servers. In my new position I support about 150 people, but I cover IBM AS400, Microsoft, Cisco, NEtworking, Firewalls, and backup. Smaller organizations tend to have one or two “do it alls” where larger organizations tend to have people who have a focused responsibility. In vermont, where I live, there are very few large organizations to work for.