The thing is that if one is seeking that which is stereotypically "redneck" one is more likely to find it in the far eastern half of the Metroplex and points east than here in Fort Worth and points west. Think Mesquite, Balch Springs and Kaufman County and go beyond into East Texas. That is the part of the state where the culture still has a heavy Southern influence. And there is even a hillbilly influence (a lot of long time families there originally came from Tennessee). Fort Worth and points west, by contrast, is more Western in its culture than Southern. Cowboys, cattle ranches, stockyards and such are something that is part of Western culture - not Southern. If one is going to use stereotypes, let's at least use them accurately.
As for stereotypes in general - I think they can be, as a general rule, ok so long as if they are used strictly for humor in a context where it is clearly well-understood that there is nothing malicious intended, which I think is the case with the movoto.com piece. On the other hand, unfortunately, the term "redneck" is often used as a slur sanctioned by a certain type of Politically Correct bigotry - and such bigots rarely get called out, because to do so, of course, would be Politically Incorrect.