Quoting from the Virtual Iron official announcement:
Virtual Iron Software, a provider of enterprise-class software for server virtualization and virtual infrastructure management, today announced it has joined the Interop Vendor Alliance, a community of software and hardware vendors working to enhance interoperability with Microsoft systems based on user feedback.
Joining the Interop Vendor Alliance enables Virtual Iron to continue to improve the performance of its technologies and solutions in customers’ multi-vendor environments. Other alliance members include Citrix, EMC, Novell and Sun Microsystems…
This news, announced same day VMware launched its IPO, is particularly important now that Citrix acquired XenSource: Virtual Iron is the first company which could be damaged by this acquisition, despite Citrix’s good intention about open source.