The forum is supposed to offset dates and times automatically wherever dates and times are written, @(you need an account to see links). A post that I make in the Pacific timezone should appear to you offset by whichever timezone you've configured for your profile. If this isn't working, then it should be on a case by case basis, and it would probably depend on its implementation in certain forum plugins as well. For example, I wouldn't be surprised if the statistics on the main page didn't synchronize timezones properly - that's a plugin that wasn't built natively into vBulletin, so we'd have to code timezone compatibility into it if it's not supported already.
Do us a favor, please. Take a look around the forum and see if you can find a few examples of where timezones aren't synchronizing in the way you'd expect. Let us know where you see that problem happening, and we'll look into applying a fix.