To add to Ober561's point:
On the VB Explorer forums, there are about 100,000 members.
I've been programming in VB for about 10 years. Though I like what I've learned so far in C, I find that VB still has it's merrits...
Take for instance, VBA (a rather crude version of VB). I build databases for a living. Out of all the guys I work with, I am the only one that writes code behind my database, all the others use Wizards to create a generic database with queries and such.
As far as commercial software, Forte is an example. The company I work for is a health insurance company. They use a Forte application to allow our Customer Service reps. the ability to browse and modify our member information... this application was written entirely in VB (with the exception of a handful of components that were written in Java).
The only drawback I see with VB is that you are required to distribute 6 basic .dll files with your application (unless the target machine already has them) whereas with C, you only need to distribute a .dll if you use something that is not native to Windows.
Believe it or not, some of the stuff you get from Microsoft is VB dependent... next time you install a Microsoft product, watch the installation and see if it installs MSVBM60.dll - that is one of the main VB redistributables.
Even better, delete this file from your Windows directory... and see which applications you have no longer run...