Wikipedia gives it as 20th Jan - with the caveat that it actually starts the evening before...

Great... I'll avoid it... if it's anything like Egyptian spring holiday.. you can't move... and all the food is gone, esp when the egyptian families arrive en masse for a long weekend!

Interfaith calendar http://www.interfaithcalendar.org/2007.htm gives it as the 20th which is a Saturday.

However, due to the differences in the start of Ramadan this year, Saudi Arabia and some other countries will be celebrating it one day earlier.

The Hejira calendar is currently not unified.

However, it is not a big celebration like the Eid holidays or Sham el Nessim.