don't let facts get in the way of a load of drivel here!
The speculation might be drivel but OTOH (and as paulmoscow has mentioned) the BEA ( French Accident Investigation Bureau) do now seem to be verifying the information that the likes of CNN have been putting out in the last day or so.
I'll see if I can track down an official BEA statement but in the meantime French media report from this morning here:
Des fumées détectées dans l'avion d'EgyptAir juste avant sa disparition
In short the report says the BEA is confirming there were ACARS transmissions indicating smoke in the cabin before communications were lost, but they are still not willing to speculate on the cause of the accident, waiting for the recorders, etc.