This is imminent, please see http://devwiki.electricimp.com/doku.php?id=cardos-release-10 for notes.
You should see your imp upgrade (short-long green blink for 10-30 seconds, then solid green for 20-30 seconds), and then come back online.
Many bug fixes and features added, including line numbers on runtime errors, sampler API, wifi powersave mode, uart string/blob writing, etc.
One other big thing to note is that the green LED will stop flashing after 60 seconds. This also means the imp is no longer listening for blinkup - you need to blinkup directly after powering up the imp.