It depends. Are you racing?

When I was racing, I was riding 6 days on, and one day off (or 10 mile recovery ride). The 6 days usually went long, short, long, short, long, long.

Now that I'm riding recreationally, I tend to follow a more exercise style workout. Ride 1 day, rest 1 day, etc. and now that I have more free time I added a day to make 4 days a week. It all depends on what you want. Races, health, muscle tone, endurance and sex drive, ride a century?