I am still putting it off. Tempted, but haven't succumbed. Moveability, and economy of space, are the main reasons I would change.
Three years ago I saw a normal 26-inch Toshiba on deep sale. It works fine, with excellent picture. I will continue to use it until it fails. Some do last, I have a 15-year-old Sony also.

A technician friend told me plasma is better. I don't know, but check it out.
Also buy from a factory-approved electronics store- stay away from those supermarts such as Wal-mart and their here-today gone-tomorrow bargains- OK for underwear or cheap everyday stuff but not for electronics.

Those extra-charge warranties that most stores sell- yes, if something goes wrong they help (one gave me an immediate replacement). But check out exactly what the store will do if you buy. Also check and see if there is a shop in your city doing warranty-approved repair on the brand you select.