I work for Georgia Tech's (I hate to use the term) incubator. Very different types of startups come out of there than YC. But media and investors come to us every day looking for new companies. Why? Because we see a lot of deals and vet them. YC does the same thing. Angels, VCs, and TC know that PG sees a lot and only accepts the best. PG is the Good Housekeeping Seal of Approval for Web app startups.