Despite having not only one, but two wide monitors, I still think its a good idea to keep lines in code short.
That does not mean a hard cut on 80 characters, but to take care that it is not much longer.
I have the following reasons
- I prefer reading "top-down" to "left-right" ... and that includes code
- my screen is usually filled with windows, so its good to have them side-by-side and still being able to see all of the code
- in some rare cases I print code ... and then I have a limit of characters per line (otherwise it looks akward...)
Am I just too old-fashioned?