It was very clear from the very beginning that the GTR was going to compete with the 911TT. It does exactly that, and beats it fair and square. Thus, anyone thinking that the M3 was going to compete with the GTR must have been really naive/misinformed. It will be interesting to see Porsche's answer soon. They will most likely increase the power.
This post should be in the M3 vs. ... by the way.