Sadly yes, two of them. The main lesson is never build a business based on advertising revenue.
We shut down http://www.publisha.com and http://www.viewshound.com after running out of funding.
We shut down http://www.publisha.com and http://www.viewshound.com after running out of funding.
That would be the main lesson only if you somehow could assert that the failure of your business is due largely to the fact that it was based on advertising revenue.
And that's how you have to think if you're supported by advertising dollars.