I have worked for a company that does 9/80 weeks for a while now, and I have to say it is a completely great way to go. For one thing an extra hour a day really isn't that big of a deal. In my old job, I'd usually get sucked into something at the end of the day that made me stick around the office for a few minutes to an hour after normal working hours (if not more) so working 9 hours instead of 8 doesn't feel that unnatural. But what does feel unnatural (and fantastic) is having a three day weekend every other week! If you are worried about not having time to get things done in your personal life, I wouldn't. I used to have a real problem scheduling doctors appointments and visiting shops that had odd hours and such during the week, but having a totally free day (while everyone else works) during the week, every other week, is actually incredibly convenient. Plus the Friday that you do work is a normal 8 hour day, which oddly enough ends up feeling like a half day for some weird psychological reason...

One caveat I will say, is that my company is pretty flexible on the start time that you work. Many people come in at 7 or 7:30 instead of the usual 8am and subsequently leave at 5 or 5:30 instead of 6pm. That kind of takes the edge off. I could see a company that expected you to work from say 9am to 7pm being kind of brutal. But overall I would NEVER voluntarily go back to a regular schedule again.

Hope this helps.

Virginia Tech has been doing this for years. The worst part is that anyone caught with this system gets an automatic Honor Code violation.
I mean, what would you name a variable that is the bottom axis of a plot. If you said "x", congratulations, you have an honor code violation. Something like 60% of the students in my programming class got a violation in one form or another.