SharePoint 2010 Public Beta Available on MSDN
Finally the public betas of SharePoint 2010 (both SharePoint Foundation and SharePoint Server), Office 2010, SharePoint Designer 2010 and Visio 2010 are available on MSDN Subscriptions, so start your download engines right now! :-)
If you don't see the download, you can use this direct link (make sure you are signed in to the Download Center before you click the link).