According to a survey by the World Justice Project, Singapore was ranked 20 out of 35 countries in the high income group for open government, and was ranked 6 out of 7 in the East Asia and Pacific region. It scored 0.38 out of a maximum of 1 point in that category. Singapore was also ranked 1st in the category of Access to Civil Service, and Order and Security.
Channel Newsasia's report on the same survey ("S'pore justice system top in global survey", CNA Jan 7 2011) failed to mention the ranking in the Open Government Category.
You can read the survey report here.