If you define competing as "what language should I used for this app" then no. VB is way better then perl for desktop apps, and perl way better than VB for text processing and web apps.

But if you define competing as "what language should I learn in order to get a job" then yes, they are competing.

PS: I know, and have used, both in different jobs, so it's not really competition because you can do both. But if you are only going to learn one, then yes, they are competing.