Not sure on timelines, but I suspect we’ll see some enhancements in April at BUILD conference. Future plans include making the product more work item-centric, building RM into TFS (eliminating the need for a separate RM server and database), making deployment workflow much more extensible through heavy focus on PowerShell and DSC, releasing deployment agents for non-Windows platforms (e.g. UNIX/LINUX), a lot more support for Azure provisioning/configuring environments).
Tons of customers use the InRelease version. Since we’ve only had the product for ~6 months and you get Standard Edition agents with Ultimate, we don’t have a lot of customers reporting they are using it yet. A couple of my peers largest customers in MN are using InRelease and swear by it. One of them (EcoLab) has been willing to discuss their success with other customers.
The previous InRelease product AND the Microsoft version work with TFS 2010/2012/2013. You need to use the version-appropriate build process templates if you want to trigger release management from Team Build.
Only if you are deploying them to Windows Server.