Due to a technicality, Lady Gaga was ineligible for the nomination of best new artist at this year's Grammys -even though she was the most popular artist of 2009. Since she was a nominee the previous year, it meant that she couldn't be one in the next. Determined to prevent another oversight like this from happening in the future, the Academy adjusted the rules, making it so that previous Grammy nominees are eligible. What's significant about this situation isn't that the rules got changed, as much as it is that the Academy recognized that the rules had to change in order to align with the shifts in the creativity time-lines of new and emerging artists.
