The Arizona Association of Realtors (AAR) Purchase Contract makes very clear which items in a home are considered fixtures, and therefore stay with the home, and which items are considered personal property and go with the seller when they move out. However, with the increasing popularity of flat screen TV's (of which we just recently jumped on the bandwagon at our house), we now have some gray area in regards to whether it's considered real property (thus staying with the home), or personal property (thus going with the seller).
The rule of thumb is this: If it's attached to the house, or if it is specifically designed or made to fit in a particular room or part of the house then it should be considered a fixture and stay with the home. But televisions in the past have always been considered personal property, mostly because they were not attached to the home in most cases, and always have gone with the seller. Now that televisions are able to be mounted on the wall they really do fit into both categories. Other than talking about fixtures, the only other mention of televisions and/or equipement that is mentioned in the contract is on Line 36 of the AAR Purchase Contract, which states "attached TV/media antennas/satellite dishes" belong to the buyer. In this case it is specifically talking about the antennas and satellite dishes, not necessarily the televisions themselves. So we go back to the arguement of whether or not the mounted/attached flat screen television fits into the category of a fixture. As I see it, it does. However, sellers are not going to be all that willing to leave televisions behind (some of which can cost thousands of dollars) just because they wanted to attach it to the wall. In some situations I might recommend to a seller, especially in this maket, if they've got a smaller sized flat screen that's attached to the wall that can be replaced fairly easily and inexpensively, to leave it and advertise the home as such to differentiate themselves from the rest of the homes in their area.
In the end, the best thing to do is to communicate the seller's intention up front; that way the chance for a misunderstanding is greatly reduced. If the seller wishes to take the television with them, then advertise it as something that does not convey with the sale of the property. Problem solved.