If he spent half the amount of money he spent on this amazing office for a kick ass UI team, he would increase sales by an enormous amount for Fogbugz. I know so many people who would switch if it wasn't so damn ugly and difficult to use. I don't think people use Lighthouse because it has better features.
Joel's priorities seem very odd to me.
It's not that Fogbugz is necessarily difficult, it's that Lighthouse is easier.
I would describe FogBugz as ugly by modern standards, because it appears to have been written a little under ten years ago. And I would describe it as difficult to use partially for the same reason, and partially because some very simple features are missing, e.g. cc'ing people on tickets and bidirectional integration with SCM repositories. The "special" features, like integration with customer email, are not important to us.
Yet what it does is not very difficult, and many other options exist -- free, for pay, hosted, or any combination thereof. I now wonder why people listen to Joel on software.
Now apart from that I completely agree with joel's reasoning regarding building a great place to work for programmers, I just think that he should also hire more designers and ui experts...