Instead of giving divs actual names, such as header, footer, rightContent, leftContent, it might make more sense to give them section and column numbers. A section is a horizontal division. A column is a vertial division. This way, it is easy to remove/add a column or a section.
The only issue I have with that is when you remove section 2 completely in the future. Everyone looking at your code wont be able to understand why it jumps from Section-1 to section-3 to say section-8. And it wouldnt be practical to rename all of your DIVs just because you removed a section or two down the road.
I think this method only works for interchangeable content.... when swaping boxes etc.
For a "linear" website however I don't think this works... It would make maintenance more difficult.
Imagine a programmer who hasn't seen your code before trying to make a change. Unless there's documentation, it will take him longer to identify sections by those names...
"Section 5-column 2" won't make much sense to him... as opposed to goin straight into "footer".
mringlein also has a good point, take a section out and the flow is gone.
i still prefer the 'named' label.. common name used, container, header, nav, sidebar, content, and footer.. so, whenever i want to edit some value in sidebar, i just open my css, and scroll down directly to the sidebar setting.. thats all! :)