The popular Amex/Twitter deal at McDonald’s is back–when you tweet #AmexMcDs, you’ll get $5 back on your next in-store purchase of $5 or more at McDonald’s with your synced American Express card. Full terms of the promo are available here.

For those unfamiliar with how Amex/Twitter deals work, see this post for a detailed explanation of how to sync your American Express card with Twitter.

Other currently running Amex/Twitter deals also include the following:

Merchant	Discount	Hashtag	Dates Valid
FedEx	Get $5 back on $20	#AmexFedExShip	8/23/12-9/30/12
Kenneth Cole	Get $20 back on $100	#AmexKennethCole	9/6/12-10/18/12
Music Hall of Williamsburg Concessions	Get $10 back on $10	#AmexMusicHallWB	8/27/12-12/31/12
SkyAuction.com	Get $50 back on $100	#AmexSkyAuctionOffer	9/4/12-12/4/12
Terminal 5 Concessions	Get $10 back on $10	#AmexTerminal5	8/27/12-12/31/12
Tommy Hilfiger	Get $25 back on $100	#AmexTommy	8/17/12-9/30/12