Anyone else ever seen this? Site Jumped up 18 million in two weeks on Alexa

Ok, client never paid me so the site became mine. Client signed it over free and clear. www.SayItAloud.com is the site. I started going to work on marketing the site and decided to check the Alexa ranking after the site was up for two weeks. http://www.alexa.com/data/details/traffic_details/sayitaloud.com My site jumped nearly 18,000,000 at the time of this posting and has continually grown

I did no black hat SEO but instead went with methods that I had done for clients. Has anyone seen a jump like this. So the next question would be whether I am underselling my advertising on the site. Right now I have it set at $55.00 for as top banner in an article, $45 on a side banner, and $35 on a base banner for a year.

The site is only going to get bigger but I still want it to be affordable. The site is 100% original, non spun, content and I want to keep the prices low for sponsors, but profitable for me.

So comments, opinions, and critiques would all be welcome.