My guess is that most products that do this aren't much further along than a weekend hack. It's pretty easy to throw up a marketing site, and it let's you quickly see if people are interested. Thing of it as a μMVP :D
Just that on my first post I saw "customers" thinking they may have been more traditional customers.
But after being informed they were YC - it made sense they were more likely load-test and POC customers that help participate in the product evolution.
