Update: Here's video of Sanford's announcement, if you missed it:
2:33 - Sanford announces he will resign as chair of Republican Governors Association, both in fairness to colleagues and due to time pressures
2:34 - Q&A - family knew pre-trip, have been wrestling with this for about 5 months
2:35 - says first time he's been unfaithful
2:36 - asked whether broke off affair on trip, says met this person "innocently" about 8 years ago
2:37 - "we developed remarkable friendship," safe confidante to email thousands of miles from Columbia, saw her three times past year, "during that whole sparking thing"
2:38 - "during the last five days of my life I spent crying in Argentina"
2:40 - "this was selfishness on my part"
2:40 - Q - did you intentionally mislead your staff about Appalachian Trail?
2:41 - they went by my original suggestion