I'm on a 9/80 schedule. Today (Friday) is my day off! Next Friday I only work 8 hours. I do really like that three day weekend every other week. Having it every week would be really awesome. A couple of sites within my company work 4/10s.
Truth is that at most jobs like the one I have (engineering technical work at an operating facility), most people find themselves staying at work 9 or 10 hours a day anyway to get everything they need done. So, the 9/80 or 4/10 works out well for people like us. The down side is that if you get in at 7, you don't leave until 5:30 or 6 on the 4/10 schedule (with the lunch break). Now, to get in at 7 with the commute I have, I would need to leave my residence no later than 6:15. This puts me waking up at 5:30, which puts me in bed no later than 10pm. By the time I get home at around 6:30 at night, I would have around 3 hours to eat and take care of real life before doing it all again.
I spend my 9/80 day doing all the things that you could normally knock out during the week after work. The nice thing is that I typically knock out everything on that day (errands, shopping, laundry, cleaning, etc), which frees up my weekends for everything else.
Just remember that you are only shifting time around. The time you generate in this schedule comes from saving time on your commute, which for me amounts to 3 hours per month on the 9/80 schedule.
R