In 1951, a man named Rudolf Flesch published the book, "The Art of Clear Thinking." Many libraries still have it. Used copies can be purchased:http://www.amazon.com/Clear-Thinking-Rudolf-Franz-Flesch/dp/B00005VFWY
The OP would do well to take a look at this book. The insights will likely be staggering.
This topic's title seems to pose the question, will the Canon EF-mount be obsolete at some undetermined time in the future. By the way, there is no word "obselences."
Disregarding the mystery of how the EF-lens mount could become obsolete multiple times, the OP then poses a wholly different question: Does Canon's introduction of a mirrorless camera using a different lens mount mean they will stop offering SLR cameras. Huh??? Canon just upgraded their low-end point & shoot line with an A1400 using AA batteries (as did the 1200 and 1300). So, will Canon now abandon cameras and start selling flashlights? Toy fire trucks with flashing red lights and sirens?
Trying to make sense of this, the only thing I can figure is the hangover from a weekend binging on dilithium crystals lasts into Tuesday.