You raise an interesting question: although the MCSA/MCSE are better known and may in fact have access to a greater total number of job opportunities, network administration is in the doldrums along with the economy and likely to stay that way as long as the economy stays down. On the other hand, programming jobs are looking pretty good right now and are expected to improve as an influx of ".NET-enabled" applications hits the marketplace in the next year or two.
Given that your proclivities and job responsibilities already lean more heavily toward development than admin, I recommend you pursue the MCAD/MCSD credentials, and that you also learn as much about XML and Web-enabled services as you can (as well as Visual Studio .NET and if you choose to stay with VB, VB.NET as well). I think these credentials will be more valuable for the foreseeable future, both in the relatively short term and in the somewhat longer term.
Editor's note: To learn more about Visual Studio .NET, visit TechTarget's VS.NET Info Center.
This was first published in February 2003