Actually, the origins of this site have nothing to do with bokeh. Rather, it started with a discussion about Nikon lens versions (I think it was about the 1.8/50).
I found it very difficult to detect differences in prime lenses by comparing the usual optical characteristics, such as contrast and resolution. Thus the idea was born to check if the lenses had different bokeh, and use that as an indicator for different optical construction.
That did not work out at all.
Afterwards, I was left with a bunch of slides showing unsharp light spots shining through tree leaves. Instead of just throwing them away, I decided to put them on the web, and thus bokeh.de was born.
The site, and the number of test images, has grown somewhat since then. I've even bought some lenses just to take bokeh test shots (perverse, isn't it?)
Since I meant to mainly show images, I never intended to translate the page into other languages. However, bokeh.com, .net, and .org were already registered to to other people, so I had to use bokeh.de.
I'm not a photographer, but rather one of those hobbyists who care more for equipment that for actually taking photos. Actually, I do like taking photos, but so far I've not produced anything of reasonable quality. But hey, I'm young (at least I sometimes feel that way), and might still learn a thing or two. If you'd like to see some of my attempts, look at my photograpy page.