Can you elaborate on what the network effects of using Visual Basic would be, actually? What domains does Visual Basic have significant network effects? How does this compare against the network effects of Perl's CPAN, which is a significant factor in my choice of programming language?
Offhand, I'd bet VB will open up a larger raw number of job opportunities than Perl. So why doesn't everybody jump on that bandwagon? After all, every major language is Turing-complete, so obviously people are just nitpicking when they could be choosing a clear winner.
So I'll pose it in different terms: why haven't you given into the network effects of, say, Visual Basic?