[ghaff]

>Do people actually write eBay?

Yes?

In my experience, publications and the like do tend to respect the capitalization and other choices of a company/project/etc. with perhaps some exceptions like the ! in Yahoo! and perhaps all caps as in NVIDIA. In the case of Wikipedia, I'd go so far as to say that they're simply wrong if they're ignoring the actual way a company name is officially styled.

Mind you, I'm not necessarily a big fan of case-sensitive everything but here we are.