The ability to execute custom scripts in order to quiesce a database as part of the Hyper-V Linux Guest VSS snapshot process. This would provide Application Consistency and not just File System consistency in Linux guests.

i.e. similar to what VMwareTools provides and what Veeam/Comvault exploit: http://documentation.commvault.com/commvault/v11/article?p=products/vsvmware/tvmwconfigprepostsnap_script.htm