I agree completely. I take the shuttle from SF to Mountain View every day (I work at Google). It's about 70m door to door each way. For the first 6 months of work I was miserable, 70 minutes is way more time than I wanted to check my RSS and Email so I was bored. Boredom kept my mind on the commute, and thinking about the time made me angry.
I decided to use the time to read books as a new years resolution. Having at least 2h a day, 5 days a week to read books has made me fly through books faster than any other time in my life. I've already read 21 books since January and I actually look forward to my reading time now! I think if I had this time at home I would not be using it so peacefully/productively, I'd probably waste it on Netflix.
That said, 70m each way is more than I need. I think 30m each way would be the ideal balance of forced mind-clearing and reasonable work-life balance.