[Lizard]

While OmniPlan and OmniGraffle are generally compatible with Project and Visio (respectively), we continue to fix issues as our users let us know about them. In particular, OmniGraffle 5 will add support for binary Visio files. OmniPlan cannot yet read the Project 2007 format, but Project 2007 can save to the Project 2003 format which OmniPlan does support, so this is not a total roadblock for most users. We also continue to find and fix smaller, sneakier issues.

You might get more response asking this in the Graffle and Plan forums.