The MythTV 0.26 Beta announcement was made this morning via MythTV.org. "We are happy to announce that 0.26-beta is now ready, although delayed due to some deadlock bugs that took longer to debug than expected. The release schedule will be updated sometime soon once the beta has had some soaking-in testing time, although the string freeze is still set for August 12."
Among the changes to MythTV 0.26 is support for a HTTP Live Streaming recorder, HLS playback fixes, a complete rewrite of the RAOP server used for Airtunes/AirPlay, recording rule templates, themes can now customize caption/sub-title formatting, and there's various other changes.
More details on the forthcoming MythTV 0.26 release are available from the MythTV Wiki.