Rated 5 out of 5 stars
Works as expected with Lightning 3.1b1 and Gdata Provider 0.31pre.
Yesterday I tried Gdata Provider 1.pre-tasks-v5 for the first time - works as well. Organizing multiple task lists is a little bit cumbersome (each list as a separate Lightning calendar), but can be done at least. The UI isn't really suitable for managing several lists. Some kind of drop down list selection would be nice, just as offered by the Google Tasks Sync plugin.