Manufacturing companies would never do anything to bolster their statistics, would they?
It is a very well known fact that the reason contrast ratios have been skyrocketing as of late is because of the way contrast is being measured plain and simple. Hell, I have a friend who was at Cedia as a vendor and asked a Sharp representative what the difference between this year and last years panels that caused the contrast increase from about 2,000:1 to 10,000:1 the representative simply said "Ohh, we just measured them with a different methodology."
Just as with receiver power ratings or speaker frequency ratings there are always other angles to the same situation that can show something in a better light. This is often what is being done with displays.
Also, Pioneer just showed an infinite contrast plasma at CES this year. Honestly that doesn't matter, how often is pure black really needed? After all, every bit of detail is lost in it. Simply put one specification will never tell you the whole story on any piece of equipment especially when it is not taken using realistic methods by a credible third party with no vested interest.
BTW Greg is dead on if a display has a life of 60,000 hours (even though some new Pioneers are rated at 100,000 hours) that translates to 7 years of use at 8 hours a day more than long enough for the average consumer.