In an announcement that surprised no one — given the predictable rhythm of such decisions — newly reelected Arlington County Board member Mary Hynes has been named the future County Board chairman for 2012.

Hynes and Board member Walter Tejada were sworn in for new four-year terms yesterday, after both winning reelection in November. The swearing-in ceremony was held in between County Board sessions last night.

Hynes will outline her priorities as chairman for 2012 at the Board’s annual organizational meeting on Monday, Jan. 2. Hynes has served as a County Board member since 2008. She was previously an Arlington School Board member from 1995 to 2006.

Separately, Barbara Favola took what may be her last vote as a County Board member last night. Favola, who was elected to the Virginia Senate in November, submitted her resignation — effective Dec. 31 — last Thursday. The resignation will allow election officials to choose a firm date for the special election that will be held to find Favola’s replacement.

The special election date is expected to be revealed by the end of the week, according to Arlington County Registrar Linda Lindberg.