The seats that will be open for election next spring are Ward I (David Jones' seat), Ward II (James Gulley's seat), Ward III (David Ragsdale's seat), Ward IV (Jim Ritchey's seat), and the mayoral seat (currently held by John Tyler Hammons). The other seat from each ward is up 2011.
Ritchey's announcement means that at least one city council seat will be up for grabs. Rumor has it that Ward I and Ward II may be open seats in the next election as well.
You can read the Muskogee Phoenix's article here.