“As of yet” is a windy and pretentious substitute for plain old English “yet” or “as yet,” an unjustified extension of the pattern in sentences like “as of Friday the 27th of May.” (from Paul Brians, Common Errors in English Usage, 2nd edn, 2008)
It simply means up until now or less frequently up until a point of time in the past, and is often used in negative sentences. Avoid and use 'yet' or possibly 'as yet'.
I haven't finished painting my bedroom yet
As yet, I haven't finished painting my bedroom
As yet, house prices haven't risen to their 2007 levels
House prices haven't yet risen to their 2007 levels
I don't plan to get married as yet
I don't plan to get married yet
The movie is as yet unreleased
The movie hasn't been released yet