One of the past winners was Sudeshna (Ganguli....?). I did go to one of her concerts in Calcutta with Kumar Shaanu.
I think she is still singing some remix albums and I did come across a couple of her albums, though I could not find any other information on the web.
nachiketar...hothat abar
Sudeshna Ganguli
This one's from Nachiketa again, but the songs are sung by Sudeshna Ganguli. The eight songs are written and scored by Nachiketa. Sudeshna is good so far as her voice is concerned. Nachiketa accompanies her in some songs with a line here and a hum there. The opening song, Jodi hothat abar, has a couple of lines snatched from Laxmikant-Pyarelal's (Mere Humdum Mere Dost) mukhda in Chalo sajna jahaan tak ghata chale, and Nachiketa interposes with the line in its original version. Some of the songs are pretty average and the lines jar at times. Ektu dekha is light, and Dristi jhhapsa and Phera mane are two of the better ones.
She also came with an album Nijhoom Sandhyay with another singer Prasoon Mukherjee in bengali.