First, I have to agree with Jim West. Caution is necessary. There is no need to rush into accepting a 1st Century CE date without first analyzing the evidence. We all eagerly await the publication from Brill, but until; we can read it and evaluate the data we should be on pause before any more speculation enters the discussion.
Speaking of speculation, Joel Watts and James McGrath have both brought up mythicism. What amazes me about their criticisms is that, from my understanding of mythicism, the dating of Mark has absolutely zero to do with the historicity of the figure of Jesus. So why would James or Joel think that this would somehow change the case for mythcists? Either they are not yet familiar enough with the mythicist arguments or they are just trying to get a rise out of people. If it is the former, I’m a little embarrassed for them both. If it is the latter, I admit, I chuckled.