I think it's super interesting to hear that they're developing software to automate traction updates. It would be so cool to be able to "gem install yc" into your Rails app (or whatever) and then have hooks that will automatically keep them abreast of user growth and engagement.

It provides really interesting opportunities for them to be proactive about giving help at the right time. For instance, they'll be able to setup rules for notifications e.g. when you're having a slowing rate of growth, or to send congratulations when you've had a strong month etc.

I imagine one of the problems in investing in so many companies is that you aren't always aware of problems before it's too late. By using software to collect metrics about their portfolio companies, they can systematize how to become aware of and help out companies where they can make a difference.