You forgot to mention the billion-dollar Skype... which can do free-as-in-beer voice calls (skype-to-skype), and simple text chat (proprietary skype protocol). Evolution-aka-outlook-clone no longer ships with Fedora from what I can gather, and Thunderbird is a good OutlookExpress substitute, but not a good OutlookProper substitute. As for text-n-voice chat, pidgin *does* ship with Fedora by default... but the core devs refuse to attempt skype compatibility (because they want microsoft to come to them... and because "you can always install the pidgin beta for windows").
But truth be told, I'm thinking that your worry that Microsoft has a death-grip on the enterprise through their exchange server is a bit out-dated. I'd be more concerned about gmailEnterprise + googleVoice + chromeOSserverEdition, than I would be about outlook + skype + win2k12, in terms of being threats to the viability of corporate-desktop Linux.
Did your company actually use RHEL6 on the desktops, or was it just a server-side thing to run the datacenter? Since it sounds like everybody was using Outlook clients, presumably the latter. But that observation ties back in with the best goals for Fedora flavors: methinks we need to have a strong focus on the CorporateDesktopFedora flavor (which currently does not even exist that I can tell), which supports central IT out of the box (including a powershell port), which tightly integrates with *both* FreeIPA as well as ActiveDir servers, which can cleanly accept GroupPolicy security constraints as well as SeLinux config, and which has all the WindowsPro bells and whistles (image-backup & drive crypto & proper SMB & whatnot).
FedoraCorporateDesktop flavor would then be able to compete head to head with Win8 clients... and FedoraCorporateTabletAndPhone flavor would not be far behind.
Re: Fedora is an echo chamber
But truth be told, I'm thinking that your worry that Microsoft has a death-grip on the enterprise through their exchange server is a bit out-dated. I'd be more concerned about gmailEnterprise + googleVoice + chromeOSserverEdition, than I would be about outlook + skype + win2k12, in terms of being threats to the viability of corporate-desktop Linux.
Did your company actually use RHEL6 on the desktops, or was it just a server-side thing to run the datacenter? Since it sounds like everybody was using Outlook clients, presumably the latter. But that observation ties back in with the best goals for Fedora flavors: methinks we need to have a strong focus on the CorporateDesktopFedora flavor (which currently does not even exist that I can tell), which supports central IT out of the box (including a powershell port), which tightly integrates with *both* FreeIPA as well as ActiveDir servers, which can cleanly accept GroupPolicy security constraints as well as SeLinux config, and which has all the WindowsPro bells and whistles (image-backup & drive crypto & proper SMB & whatnot).
FedoraCorporateDesktop flavor would then be able to compete head to head with Win8 clients... and FedoraCorporateTabletAndPhone flavor would not be far behind.