I live in a condo and work from home and the separation is very difficult. Especially when I was contracting and trying to work every waking hour.
However, I still really enjoyed the flexibility of it and still had enough social interaction to keep me sane.
Now that I am only working on a startup, it is so relaxing :) Maybe because I am enjoying the process and work instead of just trying to put in hours.
I've worked from home before and I can pretty much relate to what the article says. It's nice to do once in a while, but I much prefer to actually go to the office.
The key to working from home is to have a clear separation between your office and the rest of your life. It's ok if it crosses over (after all, that's the advantage of not having to work at an office), but they shouldn't be intertwined.