Assuming Origin can do better than the "combination" of current Mac programs such as DeltaGraph , KaleidaGraph, and Excel, I think there would be a good market for a Mac version. Just make sure it is streamlined and efficient! I use KaleidaGraph and love it because it is simple, stable, and gets the job done without a lot of fuss. DeltaGraph is also good, but has a much more complicated interface. And of course Excel has good and bad points, its bad being that it is slow and kind of bloated.
I too use a combination of DeltaGraphPro and Excel and would greatly appreciate the additional features and ease of use that this program could provide.