Citrix acquiring XenSource

I just read that Citrix is acquiring XenSource, the company behind the open source Xen hypervisor. I have a CCA (Citrix Certified Administrator certification) in Metaframe 1.8 from a few years ago but I haven't really kept up with Citrix. I have kept up with virtualization though, particularly Xen and VMWare. This new acquisition seems particularly interesting and I wonder how this will affect the open source Xen.