Guess the date we hit 4,000 twitter followers

Sunday July 11th 2010, we hit 2,000 twitter followers. I think we hit 1,000 in the middle of March.

Guess the date we hit 4,000 followers and win a free pizza. Post your guess in the comments.

You must predict the date 2 days in advance of us actually hitting the mark, and if two people predict the same date the first to do so wins. One guess per person.