Yes, both Portland and Providence Phoenixes will be continuing. In fact, I think Providence is hiring four new reporters to pick up the slack of losing the Boston stories.
The difference is that Portland/Providence have a different funding source: local advertisers vs. the national sponsors in the Boston one. The national market just dried up but the local sponsors are still buying for the moment.
I, too, feel they won't be around for the long haul, but only because all newspapers are probably doomed long-term. Especially the weeklies.