Well, it's on, but not on as if it was really on.
Heh

Hard to explain.
If 0=off, 1=on, I guess standby would be 0,2.
I don't really know the mtbf for a laptop is, but we still have laptops from 1997 or something running here. And some of them have ran 24/7 (on, not standby, but really on 24/7) for years.
They're build to last, to last long enough for them to become obsolete. I wouldn't worry about their life span.
If it falls apart, it's probably a manufacturing defect, and a manufacturing defect is only critical when it happens on your harddrive (that's what backups are for).
I recall acceptable mtbf for a harddrive is something like 200k hours.
Of course, some parts will wear of by time, like the battery of the laptop, but there's nothing much you can do about it. It will wear out, whether you use it or not.
Any computer might fail faster if you intensively use it's processor for extended periods of time. Eg. if you run some dc program.
This I gather with logic

-M