Good Morning America anchor Robin Roberts tearfully announced today on the show that she's been diagnosed with the blood and bone marrow disease MDS, or myelodysplastic syndrome. Roberts, who survived breast cancer five years ago, said she got the news the day GMA ended its sixteen-year losing streak to Today, and found out that she'd landed her historic interview with Barack Obama on gay marriage during a "rather unpleasant" bone marrow extraction prodecure. "Talk about your highs and lows!" Roberts writes in a letter titled "I'm Going to Beat This." She will be receiving marrow from her sister in a transplant later this year and insists, as she did during her cancer scare, that she's still "freaking blessed."