Hi Patrick,
Always hate that it’s bad news I report instead of good, but I’m seeing the Start Render value return 0 starting on/around the 17th. Just noticed it today when looking at the past few days of data.
While I wish it was instantanous rendering, I’m pretty sure there is something wrong somewhere. 
“Good” result/values:
http://www.webpagetest.org/result/130517_PY_QZ3/
Zero value values for Start Render:
http://www.webpagetest.org/result/130518_K9_3PS/
Thanks,
Mike
PS. As good news, all the other days have been without any issues. So you rock there. 
Keep up the great work and thank you so much for your support.
Sorry, I enabled 3D acceleration on the Dulles VM’s to fix some mobile emulation issues and apparently Chrome started using GPU acceleration for everything (which broke the paint detection currently in place).
I noticed the impact this morning when I was looking around and it is fixed now: http://www.webpagetest.org/result/130520_3F_WVG/
No worries, thanks for fixing it.
Heads-up, if your numbers take a jump, it’s because of Chrome, not your site: http://www.webpagetest.org/result/130521_TF_1645/
I just enabled support for the GPU-accelerated video with fixed paint detection. We are seeing it being slower than the software renderer though so some more investigation is in process (not sure if it is real or if it is the emulated GPU in the VM’s).