Sure, if you do want lots of forums then make sure to make use of subforums so the front page isn't too overwhelming
Your biggest issue here will be load times. I created a sports forum a while back with a forum for every team in the NFL, NBA, and MLB. On a shared host it took FOREVER for the forum index page to load. You will need at least a virtual dedicated server (about $30 per month minimum) for this or even a dedicated (starting at about $100 per month) server to load the index fast enough for people not to leave because they have to wait so long.
That would be a question for the host. I really don't know. If I had to guess, it was just the fact that it took too much processing power to render the huge forum index page. Once you were inside a forum it loaded fine. The index page was the problem.
It sounds like he wants to start with a lot of categories an build a lot of posts himself quickly. If so, then I agree it would be worth at least a virtual private host to start with - nothing too expensive, but it's a good idea to try to get at least a half decent host to begin with - you don't want to start out by driving members away!
Wow! You got some good feedback here, gonna use some myself My 2cp worth was to suggest paying some DP members to leave blog entries and/or replies. There seems to be a thriving market here for such service... plan to use them some myself.
I own a couple of forums and prefer IPB although am well versed in using vB. PM me if you need assistance etc.