Microsoft has announced it will release PST Capture, a free tool to search .PST files, import them into Exchange Server 2010 and Exchange Online and (optionally) destroy the files.
Exchange mailbox data is stored on Exchange servers – either on-premises in your organization’s datacenter, or in Exchange Online if you’re using Microsoft’s new Office 365 cloud service. Historically, Outlook users have used .PST files to store messages on their computers in order to reduce the size of their mailbox on Exchange or simply to keep an offline copy.
However, with ever-increasing mailbox sizes (see Exchange 2010 Large Mailbox Vision Whitepaper), lower storage costs and Personal Archives – the email archiving functionality in Exchange 2010 and Exchange Online, finding and eliminating .PST files is becoming an important concern for organizations. Besides preventing data loss, data leakage and theft, moving PST files scatterred all across an organization back into Exchange also allows you to respond quickly to eDiscovery requests and reduce discovery costs.
--> The rest is on the blog : http://exchangepedia.com/2011/07/microsoft-to-release-pst-capture-tool.html