The application deadline for the winter 2010 cycle is tomorrow. Don’t worry if you decide to apply at the last moment. Some of the best startups we’ve funded only decided to apply a few hours before the deadline. (In fact, way more YC-funded startups applied at the last minute than I realized, judging from this thread on Hacker News.)
Now that it’s possible to submit a late application to YC, someone who decides to apply at the last minute has a choice of submitting an application by the deadine that may not be very complete, or submitting a late application and taking more time to work on it.
I strongly advise taking the former route and submitting an application by the deadline, even if it’s not as polished as you could make it if you had more time. The odds of a late application being accepted are much lower—around 3x lower.
Our whole approach to late applications is different. We feel obliged to read all the regular applications at least moderately thoroughly. But the late applications we just have one person skim, in case any stand out as exceptional. It is much harder for a late application to get noticed.
Many of the questions on the application that we care most about don’t take much time anyway. Probably the most important questions are about what the founders have achieved before, and what insights you have about your idea that no one else seems to have. Those matter more than a polished demo, probably, and they shouldn’t take more than an hour or two to answer.