They promised ICS for the Rezound with the same timeframe. The Rezound is, arguably, a more high priority device, and we haven't gotten it yet either.
There have been numerous ICS leaks for the Rezound, so I know that phone's update is close.
The problem, IMO, is that the Rhyme can barely handle GB. They're gonna have to optimize the crap out of the ICS version before it's stable enough to release. And that could take a mighty long time.
Bottom line: don't hold your breath. I hope I'm wrong.