Medial capitals have always been around in English, but the use has exploded of late, and a lot of people think it looks silly, as though a word is missing a space or a letter is randomly miscased. It looks alright in personal names because we’re used to it—no one complains about MacDonald, DeLuca, LeBlanc, or O’Shaughnessy. But the phenomenon of medial capitals in company names is really only about 40 years old. There are many well-known examples—YouTube, PayPal, RadioShack, PlayStation, &c., but I think they succeed by sheer volume and dot-com kitsch.
The only time it really bothers me is when budding authors are trying to come up with fantasy names. They use (what I lovingly call) Dread Intercapitals alongside Dread Apostrophes and Dread Accents to make names that look like Harâk’Thür—presumably in imitation of Tolkien, who actually knew what he was doing, and had internally consistent language models.
Because there's supposed to be a space there. You can be forgiven perhaps if the things you're concatenating are not words, like ServInt does where Serv Int would look weird, but when you just take words and mash them together, that's not suddenly a brand: that's a typo.
I guess the problem is that it just gets dreary. Just to confine myself to web hosts: DreamHost. HostGator. HostMonster. HostOrca. KnownHost. StartLogic. TotalChoice.
Go on, try to say NearlyFreeHosting in one breath, no pauses. That's the name of that company. Someone actually named their company "neerlafrihostin."
You don't have to go as far as A Small Orange does, where you choose a branding that makes me think of a webcomic. You could just be like Liquid Web and Media Temple -- give me your name with those spaces intact. CamelCase is for programming languages and the occasional wiki -- and it's still ugly in those places too; I just don't see great alternatives there.