[ajxs]

> It encourages shorter names...

I can't remember my source right now, however I recall a study which indicated that having more descriptive variable names contributed more to the overall perception of code quality and legibility than nearly all other factors. If I recall correctly it was a study into code quality metrics commissioned by a large company. This strongly echoes my own experience. Naming variables like you're paying by the letter contributes heavily to making the job of understanding the code on a line-by-line basis much more difficult for other people.

For what it's worth, when I write in C/Ada/Python/Perl I stick to 80 columns. When I'm writing in OOP languages I usually limit myself to 90, and definitely less than 100.