Current Mods With VB4
 

I'm still real new to vBulletin. The only upgrade I've ever done to my forum is going from 3.8.3 to 3.8.4. I can only guess that vBulletin upgrading to a whole new number (vBulletin 4.0) is gong to be massive. Since this will be my first major vBulletin upgrade, should I expect a lot of the current mods/templates/skins I have installed on my forum to break when I upgrade to the yet-to-be-released vBulletin 4?

For this particular upgrade, you should expect most mods, templates, and skins to need upgrading before you can use them on a v4.0 board.

How many coders/designers here are good about keeping their stuff up to date?

I'm already working on upgrading my mods to be compatible with v4, and I don't even have v4 yet :D

How do you know how to make compatibility modifications if the new product isn't out yet?

Go off of the articles and blogs about what the new structure and code is going to look like. You can find some in the articles section here on vbulletin.org, and you can find more on vbulletin.com