You shouldn't see any undesirable artefacts if the broadcasters have done their job properly. The trouble is that there is no such thing as a fixed amount of overscan, so if a broadcaster decides to leave in a shot that has, for example, a boom mic creeping into the top of frame, someone will have a TV that will display that boom. Broadcast monitors have an Underscan button that you generally leave pressed so that nothing untoward on the edge of frame will escape attention. And now with streaming TV channels and stuff like the BBC iPlayer, the old excuse of "Don't worry, it will be in overscan" just doesn't work anymore.
Most, if not all, TVs - plasma, LCD or whatever, can be adjusted so that you get no overscan/cuttoff whatsoever. I know a Video Editor who had to set up his own LCD TV because it was overscanning about 20% and driving him crazy. Of course, some of controls are in software now, so you have to have a manual and take the cover off as well as being technically very capable. In the past with three-gun CRT tubes it was even more of a skill, but it can be done.
So why do some TVs come out the factory set-up to overscan so much even in this day and age when electronic circuits are so stable?
When you go to the store and look at them all lined up, how do you judge which has the best screen? I actually think some manufacturers believe the TV that overscans subjectivly has a larger screen because the picture has been blown up, and we are too stupid to notice that stuff is missing off the edges!
Because of this, Broadcasters are still having to use the safe area rules where captions have to be within the centre area (80%?) of the picture. Next time you are in a TV shop, see how much the positioning of captions vary from TV to TV.
Exactly the same compromises that home video makers have to take into account have been a pain in the backside for broadcasters since the 30's 