Priest is missing in action!
If the priest doesn't show up, and that is the only time you are able to to to Mass...does it "count" as attending Mass?
Although the obligation to attend Mass on Sundays and Holy Days still stands, the unexpected absence of a priest is not a reason to think that you have not met the obligation. After all, the congregation made the effort to be there and can be in good conscience - http://stanthonytemperance.org/?p=2730
Code of Canon Law 2183 "If because of lack of a sacred minister or for other grave cause participation in the celebration of the Eucharist is impossible, it is specially recommended that the faithful take part in the Liturgy of the Word if it is celebrated in the parish church or in another sacred place according to the prescriptions of the diocesan bishop, or engage in prayer for an appropriate amount of time personally or in a family or, as occasion offers, in groups of families."