The new portal is a completely revamped Silverlight application, just log into your portal as normal and you will be given the option to go to the new portal.
I blogged from PDC about the new items in the SDK, including more of an Infrastructure as a Service approach, allowing you to remote desktop into instance, run installs in elevated permissions mode, use your own VMs, and much more.
This is a huge upgrade and we are very excited to start leveraging this for our Event Board and other Cloud Based solutions!
UPDATE: It took all of 30 minutes to install the SDK and upgrade to the new version and get it running in the cloud! I love the new portal and the ability to Remote into my instances!