As a former WebCT admin and current Moodle admin, I think that to perform BASIC TASKS in any e-learning platform as Moodle is quite easy: CUSTOMIZATION, add/delete USERS, add/delete COURSES, get the SERVER itself good configured, including security and backups, UPGRADE Moodle,... The difficult thing is to make it get BETTER and better, and to create a colaborative COMMUNITY of users.
The most time consuming task are, to my knowledge, instructional design, content and course creation, a thing that I think that you do not have to do as a University Moodle admin. It is the teachers business to do that. Anyway, you have to train them in the use of Moodle: you can just give them documentation and perhaps create a Moodle course/community for teachers, but you will have to keep an eye on them. TRAINING and SUPPORT are time consuming tasks. Take care. An advice: do not allow phone support. Use email or forums for that. You can find yourself spending all your time in the phone. Use it just for real emergencies.
If they ask you to be "responsible for DEVELOPMENT of platform features as requested", I would assure that your only responsibility is to send an email to Martin asking how much do you have to pay for the "requested feature". If you are supposed to do that on your own, that is a full time and very hard job.
A very good thing to do as an e-learning admin is to take a look at the STATISTICS of the Web server and Moodle statistics also (such as logs), and to AUDIT from time to time the most used courses in your server, to look for success formulas and problem fixing.