Someone has stabilised dev-libs/icu-64.2 without confirming that it doesn't break any packages that depends on it. Fortunately, PyICU-2.3 has been in the tree for almost 2 months now so there should be trouble getting in stabilised quickly.
x86 stable
amd64 stable. Closing.
(In reply to Marek Szuba from comment #0) > Fortunately, PyICU-2.3 has been in the tree for almost 2 months now Stabilisation was one month late then. ;)