I had the chance to do a quick comparison between the $760 TTartisan 50mm f/0.95 lens and the $12,500 Leica Noctilux 50mm f/0.95 lens (special thanks to Vi Vante for providing the Noctilux lens).
First, a word on the TTartisan 50mm f/0.95 lens availability, since I am getting multiple inquiries every day. The lens is shipping in very limited quantities and the pre-order list is long. The current wait, if you order today, is over 30 days. I am in contact with the manufacturer and will get a notification once the lens is available.
The TTartisan 50mm f/0.95 lens is available for pre-order at the PhotoRumors Online Store (with free international shipping), Amazon, B&H Photo, and Focus Camera (eBay also has several questionable listings).
For a better view, I created a separate full-width page for the Leica Noctilux 50mm f/0.95 vs. TTartisan 50mm f/0.95 lens comparisons (the photos are also available on Flickr):
TTartisan 50mm f/0.95 vs. Leica Noctilux 50mm f/0.95 Leica M-mount lens comparison