So I went up that way around the lunch hour yesterday to check it out.
First there were only two passengers on the bus, including myself. Bring midday I suppose it is understandable that ridership would be low though.
Second, and perhaps most shocking, is that the lanes aren't even protected from other traffic! While it seemed other cars did get the message, there is nothing to stop a driver from using the lane if they so wish. Considering the time and effort to construct this, such a design is very underwhelming.
Despite this, the performance of the route was pretty good overall. I'll upload the video later, but it took about 8-10 minutes to get from Newmarket terminal to the end of the busway, depending on when you want to start counting. There was not much opportunity for the lane to show off since traffic on Davis was light during this period, but it did help it keep up with traffic. It also provides a much needed reliability and service boost to the avenue.
Returning I caught a regular YRT bus at Leslie, and while I am not sure which route it was or where it originated from, it turned onto Davis from coming from north on Leslie. The bus was well filled, about 20 people I estimate. There was a sizable passenger turnover near the hospital, and about half the bus got off at the mall one stop before the terminal.
While I do support BRT, I hate to admit it, but this really seems like a vanity project. The money could have been much better spent adding standard curbside Viva stops, and standard HOV or curbside bus lanes would have meant passengers would not have to guess at whether they should catch a standard bus by the curb or a Viva in the middle. Perhaps even skip the lane, and use the money for grade separation at the train tracks to make GO RER more possible up to Newmarket.
The only logic I can see for it at the moment is that it is cheaper and easier to build it now than when the avenue gets built up. Otherwise while it may not be as much of a boondoggle as Sheppard, it certainly is a boondoggle.