Re: That must hurt
MS and Citrix have been in bed together for many years, Every time somebody buys Xenapp licensing they also need to buy RDS CALs, so it has always been a win-win for MS. Citrix salesforce effectively selling Microsoft licenses, without MS having to pay them.
The terminal services functionality (MultiWin multi user session handling though not the crown jewels ICA protocol) originally found in Citrix WinFrame was licensed to Microsoft from Citrix.
If you ever used the TS admin tools in NT4 TS edition they looked identical to the Citrix Metaframe tools (hint: because they were the same tools).
This is an extension of their relationship.