Even if you multiple this amount by 2. Dividing this into the number of companies makes one wonder about the exposure rate in hte media for YC startups. Seems like are getting headlines and cover stories more than others.
Saying, for that only, it is worth to join YC. Let alone the weekly meetings (dinners, etc.).
Just for instance, let's just take a look at the following two CrunchBase entries:
1. http://www.crunchbase.com/person/moshe-yanai
2. http://www.crunchbase.com/company/{YC-Funded-Startup-Name-He...
While the first have sold his first startup (XIV) to IBM for $300M, Three year later, he sold his second startup (diligent) to IBM (again) for $165M, ($465M in total), the knowledge of TC about him is nearly zero. All they can tell is that for his new startup (third) he raised $9M.
On the other hand, if you'll wake up Mike arrington in the middle of his deep sleeps and ask him to name 18 YC startups he will do that right away, without even opening his second eye, wouldn't he?