This blog seems to have the best information: http://blogs.knoxnews.com/knx/silence/
20-year-old David Kernell is at the center of an online investigation into who broke in to the email account of Republican vice presidential candidate Sarah Palin and posted some of the contents to Wikileaks.

According to a report from The Tennessean, Tennesse state representative Mike Kernell told a reporter that his son, David, is the individual believed to be among those reponsible for the hacked account.
According to the newspaper, David Kernell is a student at University of Tennessee-Knoxville. The FBI and Secret Service have yet to publicly identify David Kernell as a suspect.
Here is what the hacker apparently stated:
I am the lurker who did it, and I would like to tell the story,” one person wrote in an account circulated on the Web.
In postings under the name “Rubico,” he wrote that he reset Palin’s e-mail password using her birth date, ZIP code information and where she met her husband, Todd.
When the security question was posed on her Yahoo! account, the hacker answered, “Wasilla high,” and tapped into her e-mail.
He had easily used public information to outsmart Yahoo!’s security system.
“It took seriously 45 minutes on wikepedia [sic] and google to find the information. Birthday? 15 seconds on wikepedia, zip code? Well she had always been from Wasilla, and it only has 2 zip codes (thanks online postal service!),” the hacker boasted.
“The second was somewhat harder, the question was ‘where did you meet your spouse?’ Did some research, and apparently she had eloped with Mr. Palin after college.
“I found out later through more research that they met at high school, so I did variations of that, high, high school, eventually hit on ‘Wasilla high.’ ”
“I promptly changed the password to popcorn and took a cold shower,” he said.
“Earlier it was just some prank to me, I really wanted to get something incriminating which I was sure there would be, just like all of you anon out there that you think there was some missed opportunity of glory, well there WAS NOTHING, I read everything, every little blackberry confirmation… all the pictures, and there was nothing, and it finally set in, THIS internet was serious business, yes I was behind a proxy, only one, if this shit ever got to the FBI I was fucked, I panicked, i still wanted the stuff out there but I didn’t know how to rapidshit all that stuff, so I posted the pass on /b/, and then promptly deleted everything, and unplugged my internet and just sat there in a comatose state.”