Losing charity status means the Borg will have to start paying property tax on their khs and properties.
That could turn out to be the best thing that ever happened to WT. What better reason/excuse to have for the need to sell more Kingdom Halls?
EDITED: Though, from DOYKLee's comment (above) I'm not sure that is what would result if they are unsuccessful with the case in Norway. Based on Lee's comment, I gather the Norway case is more about losing income that comes directly from the Government vs. facing additional costs of being taxed. In the USA, churches do not receive payment from Government funds, but they are exempt from paying any kind of taxes -- income taxes on receipts or "profits"; sales tax for purchases; real estate taxes on property owned.