I had this as well, stating that my password or an application required me to change it. I thought it was phishing first, but it was legit. I've never logged

I had this as well, stating that my password or an application required me to change it. I thought it was phishing first, but it was legit. I've never logged in with twitter to anywhere weird, and any apps are fairly normal (twitpic, timely). It also only happened on one of my accounts (non-business).