For as much as we all love 37s and their preaching, Scott brings up some very valid points about their actual products outside of their books and brand.
The fact that 55% (or whatever) of the market is using the tool, but you aren't part of that 55% makes the claim accurate and the tool not right for you at the same time.
I'm not even saying they should change them, but for me, there are a few feature changes that would make it way easier for me to use (and therefore a rapid fan and repeat customer).
But if you want to plan a conference booth with a graphic designer, a professional marcom event planning, and some company principals, I can vouch for the fact that Basecamp is awesome.