In an interesting development consistent with this thread's original theme, Cree has released the
XP-G3.
Datasheet. Note the S5 bin (172 lumens @ 350mA and 85°C). And this isn't vaporware.
These parts are actually available. Efficiency of the top bin would be 180 lm/W @ 85°C and 190 lm/W @ 25°C. If you want to look at CRI 90 LEDs, even there you have the R3 bin (122 to 129 lumens @ 350 mA and 85°C) available which equates to an efficiency in excess of 125 lm/W.
We've come amazingly far in the nearly 13 years since this thread was started. 60 lm/W existed only the lab. Production LEDs were only at 20 to 30 lm/W. Nowadays 100 to 160 lm/W is pretty common, depending upon CCT and CRI.