We've just released SQL Server 2008 (it feels great by the way!) and there have already been many e-mails asking us where to find Report Builder 2.0.  You can find an update on the release plan for Report Builder 2.0 on the main Reporting Services Blog:

http://blogs.msdn.com/sqlrsteamblog/archive/2008/08/07/report-builder-2-0-release-plan-update.aspx

Take care and good luck,

-Lukasz