Correct, Ping contributes to the forked driver. In fact, all of Wacom's commits to the X driver so far come from Ping and given the number of commits that's actually quite an amount. It is fair to say that she's sacrificed a lot of her freetime for me to go at this development speed and I am very grateful for that.
Kernel backports are still being developed in the linuxwacom and the input-wacom tarballs (the latter is kernel patches + xf86-input-wacom-<newest>).
But Ping is also active pushing patches to upstream. Alas, this tends to take a backseat when it comes to pushing device support into linuxwacom/input-wacom backports for Wacom's customers. The Bamboos are the best example here, having support in the linuxwacom backports long before upstream got the patches. Funnily enough, IIRC both patchsets were written by community members which illustrates the need for a "kernel patches need to go to LKML" message.
The last version announced on the lists is 0.8.8 in June 2010 which is later than the git repo for linuxwacom. I _think_ the git repo for linuxwacom was a once-off import that never actually replaced CVS but I can't prove that at this point since SF CVS is still offline. I do get irregular private emails from Ping where she mentions she is still working on linuxwacom, but tbh I've stopped checking linuxwacom's CVS a long time ago...