For example, in early November, Qantas grounded its entire fleet of Airbuses after a plane lost part of an engine and had to land in Singapore minutes after takeoff. Alarmed passengers tweeted from the airport, triggering a social media firestorm.

"While Airbus did respond, they were slow and didn't monitor the conversations," Issokson says. "It's incumbent on large global brands to engage in these conversations immediately. You ignore them at your own risk. If we see an issue arise online from a consumer, we work to solve that problem, whether directly or with our partners."

However, this form of communication is so new -- and the amount of spam and random chatter so large -- that legitimate inquiries sometimes go unheard. In November, Jennifer Laraway tweeted: "After a decade w/@MasterCard, I'm shopping for a new credit card w/a killer travel reward pts prog. Any suggestions? #visa #amex." Even with all those tags, she received no response.

"Trying to redeem my points was such a hassle that I put the request out for other options," Laraway said in an interview. "It's not a huge deal to me, but it would make all the difference if they reached out. Humanizes the corporate giants, you know?"

Tips for effective tweeting

Langlois says banks and credit card companies are slowly learning to use Twitter effectively, but missed opportunities are still fairly typical. If your first tweet misses the mark, try again.

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A few tips for getting problems resolved quickly on Twitter:

  • Stay on point: "Even though a Twitter post is 140 characters, you can still be heard," says Buster of American Express. "Be concise and to the point."
  • Tag appropriately: Search related Twitter accounts before posting. Want to dispute a charge on your Bank of America American Express card? Adding @AskAmEx and @BofA_Help will get your complaint spotted faster and channeled appropriately.
  • Monitor responses: "If you would like an issue resolved quickly, be sure to check Twitter often," Buster says. Twitter monitoring applications such as HootSuite or TweetDeck can make this easier.
  • Don't be surprised if you're asked to take it offline: A standard response from Twitter-based customer support is a request for you to "follow" a specific account (AskAmex, etc.) to enable direct messaging (DM). "Please don't be frustrated if we ask to take you to DM," Buster says. "It's intended to secure the privacy of your information."
  • Don't overshare: "A key tip for consumers is to be mindful that Twitter is not a secure channel," says Pam Girardo, spokeswoman for Capital One, which introduced a Twitter service handle (another term for user name) last July. "We remind consumers not to post sensitive personal or financial information such as Social Security number, account numbers, etc."

How to find your card issuer on Twitter

Most of the nation's largest credit card issuers and networks can be found on Twitter. Below is a list of Twitter usernames or hashtags that can be used to get in touch with the issuer of your choice.

Issuer / networkUser name and/or hashtag
American Express@AmericanExpress, @AskAmex, @AskAmex_UK, #amex, #americanexpress
Bank of America@BofA_Help, @BofA_News, @bankofamerica (inactive), #BOFA, #bankofamerica
Capital One@AskCapitalOne
Citi@Citi, @Citi_Forward, @CitiGTS, @CitiCardsCanada, #citi
MasterCard@mastercard, @MasterCardNews, #mastercard
PNC Bank@PNCNews
USAA@usaa_help, @usaa
Visa#visa (No official Twitter handle)
Wachovia@Wachovia, #wachovia
Wells Fargo@Ask_WellsFargo, @WellsFargo
Other credit card-related hashtags#credit, #creditcard, #creditcards, #personalfinance, #debit, #giftcards

This article was reported by Cathleen McCarthy for