I read in another thread (don't remember which one, sorry!) that the OP of that post hasn't had a chance to do the Subaru wave to another driver yet.
Now, I'm not quite sure what the wave is (I guess we can't exactly do the headlight bobbing like the Miatas), so this evening I just gave a slight shake of the peace sign to an oncoming Crosstrek while driving on Eglinton. Even later on the DVP, a couple pulled up beside me in their Crosstrek and we smiled at each other while traveling at 90km/h . It was legit