Well from what Ive seen and experienced, programmers get paid alot more than a network admin does however you are much more expendable as a programmer.  Theres alot of programmers out there but as far as people that have theyre MCSE (networking) the jobs pay good and theyre more stable.  Alot of companies will hire alot of programmers at once paying each a large sum of money and then when that particular task is complete they drop ya.  In networking theyre are so many areas to go into.  Networking is a very general topic and I suggest getting MCSE certs and CISCO certs like the CCIE (very hard, extremely high pay).  For Programmers the big thing now is XML and VB.