PST Capture helps you search your network to discover and then import .pst files across your environment - all from a straightforward admin-driven tool. PST Capture will help reduce risk while increasing productivity for your users by importing .pst files into Exchange Online or Exchange Server 2010 - directly into users' primary mailboxes or archives.

More detail here: http://blogs.technet.com/b/exchange/archive/2012/01/30/pst-time-to-walk-the-plank.aspx