We'll preface by pointing out that the Antique Maps Project within HistoryGeo.com does indeed contain some maps for many states not covered by the First Landowners Project (and will eventually have maps from all states).
As for the First Landowners Project, it is ongoing; it has mapped approximately 8 million landowners among 17 states at the time of this writing, and will continue to grow. Our first priority is to map data which we have already acquired, namely the original landowners indexed either by the Texas General Land office or the United States Bureau of Land Management, which includes records for the public land states.
Records for remaining states (which were formed from the original U.S. colonies) which would allow the bulk mapping of original landowners, either do not exist, exist in non-digitized form, or have other constraints which will make their acquistion and mapping a very costly and time-consuming task. Nevertheless, we intend to approach all relevant repositories of the data necessary to map early landowners in all states, and to ally ourselves with volunteer organizations willing to help compile the data into a format that we can map.
Do you have suggestions or contacts to help facilitate mapping in states we've not yet addressed. Please email details to us at firstname.lastname@example.org.