Actually, the name "theme park" is not used in the official title; it's simply a description that was provided by the person who wrote the article about it. The real name is "Dickens World," which is ok. I personally like Karyn's suggested name of "Dickens Historic Village" or something of that manner a lot better.
All the same, the idea of a theme park might conjure up images of roller coasters and such as Tbunny suggests. To me, however, the name "theme park" when applied to places like Six Flags over Texas is a misnomer. Six Flags is an amusement park, not a theme park. It may have had a theme once in the original Texas park (which was divided into six regions, each based on a historical period of Texas during which Texas was ruled by different nations, and hence different flags), but these days there seems to be very little historical or cultural aspect to the parks at all.
I wish there were more actual theme parks and fewer amusement parks, personally. Rides can be great fun, but amusement parks are often missing the imaginative spark you find at theme parks or historical parks like Colonial Williamsburg or the average Renaissance Faire. If they want to throw in a couple of period games are pony rides or something of that manner, that's fine. But I think shops with real people producing and selling clothing goods that would really have been used during Dickens' time is a lot more interesting, both to adults and children alike. Heck, it can even be interesting for adolescents if you throw in a few sword fights and some baudy humor.