Yup. Tab or space. Or in the case of "space" -- how many space characters? Also recently debated on wp-hackers mailing list when Matt released the WordPress coding style, every single programmer seems to have his/her own style. For me, a Python programmer who follows PEP 8 religiously, I like my code to have 4-space shift and every single line has to fit into 80 columns. Somehow it also affects me when I code in other languages...
Now back to elastic tabstops. It is basically trying to create "tables", and it introduces the concept of "columns" together with "rows" or "lines" of text. A <TAB> character puts the following text into the next column on the same row, so that text in the same column aligns properly vertically. A new line character basically starts a new table with a different set of column width. Very neat.
Don't think it is going to work too well with older editor that has fixed tab width. Not sure how it handles complex situations like "column-span" to allow omitting a tab or two.
I'll stick with my Vim 7 for now :)