[brianogilvie]

Bold projects are those that are available--either they have no start date or the start date has arrived. Gray italic projects are pending or on hold: they either have a start date that has not yet arrived or you have placed them On Hold with the contextual menu or Inspector.

Purple actions are Next Actions: they're the next thing you can do in the project. Blue actions are Next Actions in single-action containers (all actions in such containers are Next). Black actions are available but not next. Gray italic actions are unavailable, either because they are in a sequential project but are not the next action, or because they are pending, or because they do not have a context assigned. Red actions are overdue, orange actions are due soon. (How soon is a preference you can set.)