I'm surprised this thread keeps going. The guy that started it did not understand the term and took offense to it. Maybe he should have and maybe not.
A checkbook modeler is not someone that flys ARF's or has planes built for him, or anyone that spends a lot of money on the hobby/sport. It is aimed at the guy that does not realize that you can not buy ability and that there is a learning curve associated with different types of aircraft. Some go through the learning curve faster than others and it has nothing to do with time in the hobby.
There is a thread of RC defintions in the Humor Forum, and this thread is heading for it.