Lately, the "curse" hasn't really been present. (I couldn't get the article to open so I'm sorry if I repeat something that was in there.)
Most of the BNA winners from this decade have had and still do have success. Christina Aquilara (2000), Alicia Keys ('02), Norah Jones ('03), Maroon 5 ('05), John Legend ('06), Carrie Underwood!!!
('07), Zac Brown Band ('10) all still have a lot of success. Sure they may have some album that isn't up to par with their previous work but everyone eventually does.
Here are some I didn't list up there and the reasons I think they're "unsuccessful": Shelby Lynne won in '01 (somehow she beat Brad Paisley and I wouldn't say she was really successful to begin with lol), Evanescence won in '04 (their next album did do well, I didn't know they even broke up but almost every band eventually breaks up), Amy Winehouse won in '08 (she hasn't released anything since her Back to Black so it's not really fair to judge, I guess you an consider her personal life as part of the "curse" but I think it was like that before she won so there's no difference) [she beat Taylor Swift so it's not really the end of the world or a correct representation either], Adele won in '09 (her follow-up album is set to be released next week and on itunes at least it's in the top 10 with only pre-orders, her single is also in the top 10, she won more because of critical success than her commercial success because her sales were moderate, plus the U.S. never seems to keep their interest in artists from the UK no matter how huge they are over there, ex: Leona Lewis, Kylie Minogue) [another shocker here - she beat Lady A]
Esperanza Spalding was never a huge act so it wouldn't be surprising to never hear from her again. How many people that you know listen to jazz? She probably does have a huge following compared to other jazz artists but I don't listen to jazz so I don't know.
Tee, Gretchen Wilson was only nominated for a Grammy but lost to Maroon 5.
