Don't look on Numbers, but on the specs.
But to answer your question, it's sometime important and sometimes not.
Here: ASUS Sabertooth Z77 = 3th gen Intel core processor (i7 3770, i5 3570, etc) with socket LGA 1155/1156
BUT an ASUS Saberooth Z87 = 4th gen Intel core Processor( i7 4770, i5 4670, etc) With socket LGA 1150 (5 less pins, so a 3th gen won't even physicly fit in the socket on the Mobo)
So, sometimes you need to read the numbers, sometimes not.
Some have USB 3.0, some not, some have PCI-E 3th gen, some not.
So you need to know the specs to know what Number is better then the other.
HERE: It's like a book title. Once you know the story, you just say the title, no need a resume anymore.
So if you know the specs of the Z78 and the H77, you can just say the Number instead of the whole specs!

It's like a game Version, it's to difference them by NAMES instead of specs, but sometimes its like just the number of ram slots that changes...
So no big deal
