I just spoke with a very helpful 1K agent who actually read me the "Soft Launch" announcement for Cross Carrier SWU. The soft launch (and notice to the agents) started today.
I could transfer a 2011 CO SWU to UA over the phone.
It is currently only for SWU - the announcement did not mention regional upgrades.
Unfortunately I could only waitlist for a flight 3 months out (it was to Hawaii, and CR1 eligable, but I couldn't transfer those). 1st was 1/4 full (6 of 24) but not made available.