With painting, the identity of the painter goes along way towards valuing the work. So there are some distinct similarities, but let's not fool ourselves, domain names are not paintings. Instead, they are a unique piece of intellectual property born of the Internet age, and must be treated as such. So the domain name industry must develop its methods of valuing names, and only draw on other industries where appropriate. The single biggest problem with the appraisal industry at the moment is that reliable statistics for sales of domain names are very hard to come by.
Every market relies to some extent on knowing previous sales values to predict future sales values.
The art market only knows how to value the next Van Gogh sale because they knew what the last one sold for. Most databases are very small, and this makes them statistically error-prone. Again, if you really want to know the value of Football vs. Basketball names using sales values, knowing the value of three transactions is simply too small a sample - the likely error rate for such a sample size is huge. On the Internet, things change very quickly, and that includes sale prices. The concept of 'similar' names is a very difficult one for domain names.