This might be a bit late, but just in case you missed this one and did not get the email from Apple – please do have a look! You don’t need to purchase the DVDs if you missed this years Apple WWDC session. To access them, all you need is a registered Apple developer account from – http://developer.apple.com/videos/wwdc/2010/. Grab them in both low and high definition, and if you don’t have an account ask your friendly neighbor or get on Youtube or some other video sharing sites to see what is uploaded there 
Here is the link – Must Watch WWDC 2010 Keynotes!