I wouldn't like to go with a forum that doesn't have many users that don't speak english, would make it harder for hacks and support if it is mainly big in germany.
I didn't say it doesn't have many users who don't speak English.

They've actually a forum specially for English speakers, and another specially for German speakers.
http://www.woltlab.de/en/forum/ - English
http://www.woltlab.de/de/forum/ - German
The English one isn't as active, nor does it have as many members, however there are quite a few, and all the creators do speak both English and German and also reply to the questions at the English forum.
http://www.woltlab.de/products/burning_board/demo/acp/
The only thing is the admin panel isn't as good in my opinion; I don't know the new vB admin panel, however the one for vB2 was a lot nicer. But that's just me I guess.
Hacks wise, WoltLab do offer some official ones, and also there is a pretty large one with an English speaking community:
http://www.wbbmods.com/
I remember I was checking out that forum about a year ago, but for some reason I thought it was CGI. Is there another similar forum that is CGI instead of PHP?
Heh, no idea why. Only ones I know of are Ikonboard and UBB which are CGI. I'll try and see what I can dig up in regards to CGI forums like wBB.
Their prices seem a lot cheaper than vBulletin.
Yes, I just checked myself and they are much cheaper. Firstly they don't have a leased license system, only an owned one. Secondly, it's about $62 for wBB and $160 for vBulletin (wBB Professional license and vB Owned license); but then again vBulletin does have that name, and everyone knows it. wBB is only very popular in Germany, and has a smallish English speaking following.
Has there been much progress on the latest version of phpbb?
Well, all phpBB 2.0.x are practically the same, except the newer versions are simply bug fixes and security updates. There has been a lot of progress on phpBB 2.2, and they're in the very final milestone; which is very nice I think. When phpBB 2.2 comes out, I'll see whether I'll use it or go to a paid forum board such as wBB or vBulletin (Will more likely be wBB though). There are a lot of new features in the new phpBB I think, but I think they have the perfect balance and it doesn't seem bloated at all.
http://area51.phpbb.com/phpBB22 - You can track all progress there.
I was following it for afew months but there wasn't much happening and bugs weren't getting fixed, I was going to wait until that was out instead of changing a site to vBulletin, but it was taking a lot longer than I thought.
All the bugs and so on will be fixed when it's released. Also another reason for it taking so long with phpBB 2.2 is the fact they are rewriting a lot of the code to make it a lot faster and cleaner. They also don't want people using the CVS of phpBB 2.2 because there are plenty of bugs which need to be fixed however don't worry, when it's released all the known bugs will be fixed.
Hmm... the more and more I read about wBB, and look into it, the more I like it. I used to use it when it was freely available; however then went elsewhere, etc. as it does happen. There are only a few things I don't like about wBB, such as the admin panel and also the user panel. However, featurewise I'm pretty sure it has all the features vB2 had, but I've no idea what new features vB3 has.