just so you know, though you're right that it is and has been a factor, you're not totally correct.
http://lgknowledgebase.com/kb/index.php?View=entry&EntryID=3012
please read the entire article. i don't own an lg tv but, that article along with other sources i found in my digging, does validate what myself and others using hdtv's for monitors are saying. that article also shows how people can avoid the problem.
Well going by this article gyrene posted the link for.... which is 2 and half years old... there is/was an issue. Even then work arounds where common sense, don't over drive your system and try to make it do something it was made to do. Keep the resolutions at native settings, use VGA connections and such. In the 2.5 years technology has advanced, just a bit. I'm sure the TV's are much better, and they also take into account.... the non-bargain basement type anyway.... that people are going to use them as both computer/game monitor as well as the "tv".
Game systems have advanced as well, not to mention what you can do with computers and their video systems.
Why don't we just round this out with, if you use a cheap tv, or a computer system that is not at least average in performance you may run into some issues with "processing lag". On the other hand if you buy a decent tv with a computer that has a real video card in it you most likely won't have an issue.