Yes, but within that base it's significant. Just as within other bases the corresponding number would be significant.
This is important because if you operate a system universally with the same base, the significant number begins to take on an objective importance intra-system.
Stated another way, it's mathematical semantics, the same as arguing an idea is not significant because you can express it in a multitude of different languages, each having an arbitrary words.
Developing via Django (Python) or Rails (Ruby) is similarly predisposed to making one think it's all relative, but when you look closely, the framework doesn't matter at all - there are universal abstractions inherent in web development.
The representation is arbitrary and insignificant, what is significant is what the number or word represents, and what you can do by unraveling it.
Yes, but the other number will have a similar number of digits in whatever base you choose. More precisely, the number of digits will be multiplied by ln(10)/ln(base) for both numbers.
Irrelevant. Two numbers with the same number of digits when expressed in base 10 will necessarily be within a factor of 10 of each other. This is just a different way of saying these numbers are close.