It would seem they're only putting Samsung's into the latest iteration, but in the case of lel62 the command isn't giving a result. This could mean he has an LG, but the output is formatted differently. What you can try is break the command apart to see what changed. For example try this:
ioreg -lw0 | grep "EDID"
You should get an output like this:
| | | | | | | "EDID" = <00ffffffffffff0006100fa00000000010150104a5211578026fb1a7554c9e250c505400000001 010101010101010101010101010101ef8340a0b0083470302036004bcf1000001a000000fc00436f 6c6f72204c43440a2020200000001000000000000000000000000000000000001000000000000000 0000000000000000e700000000000000000000000000000000000000000000000000000000000000 004c503135345754312d534a41320a200044434e333330313031335446445233414b0a2020202020 00000000000000000000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000>
| | | | | | "FeatureControl" = {"GPUInterruptHandling"=1,"UseInterruptFilter"=1,"EDPDownSpreadDisable"=0,"Fast DisplayDetectDisable"=0,"SpreadON"=1,"PowerStates"=1,"IgnorePanelTimings"=0,"Gam maAdjustDisable"=0,"DisableDynamicFBC"=0,"RCxEIModeEnable"=1,"EnableDeepDisplay" =1,"MaximumSelfRefreshLevel"=3,"DPM"=1,"DeepRC6"=1,"CachedEDIDDisable"=0,"ASRDis able"=0,"Gamma"=1,"FBC"=1,"EnableConnectionState"=1,"RenderStandby"=1,"SetRC6Vol tage"=0,"UseProgrammedCoefficients"=0,"Watermarks"=1}
| | | | | "IODisplayEDID" = <00ffffffffffff0006100fa00000000010150104a5211578026fb1a7554c9e250c505400000001 010101010101010101010101010101ef8340a0b0083470302036004bcf1000001a000000fc00436f 6c6f72204c43440a2020200000001000000000000000000000000000000000001000000000000000 0000000000000000e7>
Then you can take it a step further and try this:
ioreg -lw0 | grep "EDID" | sed "/[^<]*</s///"
Which should give you something like this:
00ffffffffffff0006100fa00000000010150104a5211578026fb1a7554c9e250c50540000000101 0101010101010101010101010101ef8340a0b0083470302036004bcf1000001a000000fc00436f6c 6f72204c43440a202020000000100000000000000000000000000000000000100000000000000000 00000000000000e70000000000000000000000000000000000000000000000000000000000000000 4c503135345754312d534a41320a200044434e333330313031335446445233414b0a202020202000 00000000000000000000000000000000000000000000000000000000000000000000000000000000 00000000000000000000000000000000>
| | | | | | "FeatureControl" = {"GPUInterruptHandling"=1,"UseInterruptFilter"=1,"EDPDownSpreadDisable"=0,"Fast DisplayDetectDisable"=0,"SpreadON"=1,"PowerStates"=1,"IgnorePanelTimings"=0,"Gam maAdjustDisable"=0,"DisableDynamicFBC"=0,"RCxEIModeEnable"=1,"EnableDeepDisplay" =1,"MaximumSelfRefreshLevel"=3,"DPM"=1,"DeepRC6"=1,"CachedEDIDDisable"=0,"ASRDis able"=0,"Gamma"=1,"FBC"=1,"EnableConnectionState"=1,"RenderStandby"=1,"SetRC6Vol tage"=0,"UseProgrammedCoefficients"=0,"Watermarks"=1}
00ffffffffffff0006100fa00000000010150104a5211578026fb1a7554c9e250c50540000000101 0101010101010101010101010101ef8340a0b0083470302036004bcf1000001a000000fc00436f6c 6f72204c43440a202020000000100000000000000000000000000000000000100000000000000000 00000000000000e7>
And finally you can try this:
ioreg -lw0 | grep "EDID" | sed "/[^<]*</s///" | xxd -p -r
Which will give you a more raw result:
????????!xo??UL?%
PT?@?4p0 6K??Color LCD
?LP154WT1-SJA2
DCN3301013TFDR3AK
????????!xo??UL?%
PT?@?4p0 6K??Color LCD
If they're only using Samsung I wonder what they'll be putting into the first gen rMBPs next year or the year after when we come back with IR problems. I've still got 2 years of AppleCare, so if the IR does come back I wonder if they'll even have any LGs to give me.