With the release of XenDesktop 7 a lot of organisations are probably trying to make the decision whether to implement / migrate to XenApp 6.5 or go straight to XenDesktop 7.
Below I have tried to compare the most significant features that are in XenApp 6.5 but not in XenDesktop 7 and vice versa.
XenApp 6.5 vs XenDesktop 7 App Edition
*StoreFront 2.0 has been released with XenDesktop 7
** See here for details
Note – To utilise Feature Packs you will need to have a Subscription Advantage date that falls after the burn in date of the Feature Pack.