Definitely. Realize also though that I would consider "thinking about a problem" as also being part of work. The cool thing with our type of work - which even though I am not into the code anymore, I still do work out algorithms and architecture - is that I can do that while running or showering or driving. You don't have to be typing to be working.
Yeah, it seems that most people who think that they work 80 hour weeks do so because they count pretty much any waking activity as "work" if they occasionally think about work during it.