Well, when you consider that most semiconductors have an anticipated operational lifespan of 5-7 years, and the surface contains many such components, 2 years is well into middle-age.
So, still within the 5-7 year range? An operational lifespan is a timeframe in which most of the objects in question are expected to still work, not the timeframe by which most have failed.
If it continues to work for another 5-7 years, that's when you're getting into the "sturdier than average" realm. Your laptop could be a micron's worth of a whisker away from shorting itself out - you won't know until it happens.
Perhaps I should have stated my earlier point differently, but 2 years is still not a small portion of the lifespan of your average computer.
Funny, my 7 year old laptop seems to be running just fine.