There is no argument.
They are all video games. Period.
Some games may be more difficult then others, but they are all still games.
The fact that you have to convince them of something makes it just a struggle on your part, and eventually you'll just get pissed off.
My advice is to get new internet friends =)
Predictions For Last Full Week of Sales in 2010)
WII - 80.35 Million
360 - 43.88 Million
PS3 - 41.40 Million
More terrible predictions coming Jan. 2011!!!