well, i went from UBB to vB, and heres what I have to say
I didn't, and still don't, know anything about Perl/CGI, but I became pretty descent when it came to hacking and customizing my UBB(I can show it to you if you want)
I know absolutely nothing about PHP, and I'm totally lost at the moment when it comes to hacking, but I'm new to it, so I'll get better. Customizing on the other hand is completely template driven, and is a heck of alot easier to do than UBB.
Overall, vB is a much greater product and is extremely easy to use. The only thing it lacks is a "nice to look at" control panel