I still prefer to not have spaces in file names. I then don't need to use quotes or escape spaces when typing the file name in the shell.
tab key for the win
backslash-space isn't any harder to type than shift-underscore.
Or you could just use the dash or period as delimiters.
Because nobody else ever does? Windows apps, linux apps, javascript libraries, etc etc do not put spaces in filenames. The only spaces in filenames I have for downloaded files on my computer are the people that insist on sending me an excel document full of jpg screenshots.